Dam stability data monitoring and processing system and method

Abstract

The invention discloses a dam stability data monitoring and processing system and method, and relates to the technical field of dam safety monitoring, and the method comprises the steps: firstly, respectively obtaining instrument and image data, and analyzing the obtained corresponding displacement data; then establishing a projection relation between a displacement meter measuring point and a surface identification point, constructing a displacement constraint matrix, and constructing a corresponding dam finite element model; and finally, constructing a proportion value by using a stress-strain result output by the model, constructing an abnormal marking rule according to the proportion value, and marking and early warning an abnormal region of the dam. By means of the design, the projection relation between the displacement meter measuring points and the surface identification points is established, the displacement constraint matrix is constructed and serves as a displacement constraint condition to be applied to the finite element model, then the accurate dam finite element model is constructed, the proportion value is constructed through the stress-strain result output by the model, and the abnormal marking rule is constructed. And the abnormal area in the dam structure can be effectively identified.

Description

Technical Field

[0001] The present invention belongs to the technical field, and specifically relates to a dam stability data monitoring and processing system and method. Background Art

[0002] As an important water conservancy infrastructure, the stability of a dam is of crucial significance for ensuring the safety of lives and property in the downstream area and the sustainable development of the economy and society.

[0003] However, although the existing dam stability monitoring methods have achieved stability monitoring to a certain extent, the collection of monitoring data often relies on manual regular inspections, which is not only inefficient, but also difficult to achieve real-time and continuous monitoring, and it is also difficult to comprehensively process and analyze multi-source data. The data processing and analysis means are relatively backward, mainly relying on manual experience and simple statistical analysis, and it is difficult to deeply mine and comprehensively evaluate a large amount of monitoring data. There is a lack of constructing a corresponding dam finite element model for analysis and a lack of discovering potential safety hazards. For this reason, a dam stability data monitoring and processing system and method have emerged, which can realize an automatic collection, intelligent processing and abnormal detection and early warning of dam stability data. Summary of the Invention

[0004] The present invention aims to solve at least one of the technical problems existing in the prior art. For this reason, the present invention provides a dam stability data monitoring and processing system and method to solve the following technical problems: Although the existing dam stability monitoring methods have achieved stability monitoring to a certain extent, the collection of monitoring data often relies on manual regular inspections, which is not only inefficient, but also difficult to achieve real-time and continuous monitoring, and it is also difficult to comprehensively process and analyze multi-source data. The data processing and analysis means are relatively backward, mainly relying on manual experience and simple statistical analysis, and it is difficult to deeply mine and comprehensively evaluate a large amount of monitoring data. There is a lack of constructing a corresponding dam finite element model for analysis and a lack of discovering potential safety hazards.

[0005] To solve the above problems, the first aspect of the present invention provides a dam stability data monitoring and processing system, including the following modules: Instrument data acquisition module: A variety of special instruments are installed in the internal environment and external environment of the dam respectively to obtain corresponding data; Image data acquisition module: Use a drone equipped with an infrared camera to take low-altitude photos and measurements of the dam and its surrounding environment to obtain image data; Instrument and Image Data Analysis Module: Preprocess the data of displacement gauges, set CGC200 as the global standard, deploy identification points and decompose and record displacement vectors. After correcting the UAV images, identify the identification points, extract feature vectors, and use the SIFT algorithm to match and determine the displacement; Dam Monitoring and Analysis Module: Extract and interpolate the data of displacement gauges within the time window for alignment, establish the projection relationship between the measuring points of displacement gauges and the surface identification points, construct a displacement constraint matrix, and apply it as a displacement constraint condition to the finite element model. By obtaining relevant information about the dam, determine the loads and boundary conditions, use professional software to construct the finite element model, and analyze the stress and strain results; Abnormal Marking Construction Module: Calculate the corresponding ratio values based on the analysis results of stress and strain, and construct abnormal marking rules according to the ratio values.

[0006] Furthermore, the instrument data acquisition module includes: According to the dam monitoring requirements and structural characteristics, install displacement gauges, strain gauges, piezometers, and thermometers at key positions inside the dam body respectively; install float-type water level gauges and total stations at key positions outside the dam body respectively; Set the data acquisition time interval to collect data every half hour, transmit the data to the monitoring center via wireless communication, set up a local server in the monitoring center, and write the acquired data to the local server in real time through the Modbus / TCP protocol. Perform a full backup of the database to the local NAS at 1:00 am every day.

[0007] Furthermore, the image data acquisition module includes: Conduct a comprehensive survey of the dam and its surrounding environment to determine the takeoff and landing points of the UAV; combine the shape, size, and key monitoring parts of the dam, and use the grid-based flight route planning method to determine the flight parameters of the UAV, including flight altitude, speed, and heading; The operator controls the UAV to fly according to the planned flight route, monitors the flight status of the UAV and the imaging of the infrared camera in real time through the video transmission system, takes pictures of the area with surface identification points on the surface every half hour at the set time interval to obtain the image data of the dam surface. After the flight is over, label the image data stored in the camera memory card, including the shooting time, location, and shooting angle; use the same storage and backup methods as in the instrument data acquisition module, and perform denoising and image enhancement processing.

[0008] Furthermore, the instrument and image data analysis module includes: Perform data cleaning and data conversion operations on the original data collected by the displacement gauges; set the dam design coordinate system CGC200 as the global standard, and deploy at least 4 permanent surface identification points on the dam surface; Determine the relationship between each direction and the coordinate axes at each displacement gauge monitoring point. According to the vector decomposition principle, decompose the total displacement vector into each coordinate axis direction. Based on the decomposition principle and the determined coordinate system, calculate the magnitude and direction of the displacement components of each monitoring point in different directions; create a data record table for each monitoring point, and record the displacement values in the x, y, and z directions and the corresponding timestamps respectively. Perform geometric correction and radiometric correction on the images captured by the UAV. Using image recognition algorithms, automatically identify the pre-set surface identification points in the corrected images. Adopt feature extraction algorithms to extract the central coordinates, gray-scale features, and texture features of the surface identification points as the image feature vectors of the surface identification points; according to the feature vectors of the surface identification points in the images of different time series, use the SIFT-based matching algorithm to determine the position changes of the surface identification points in the images taken before and after, and calculate the displacement data of the dam surface.

[0009] Further, the construction of the displacement constraint matrix, which is applied to the finite element model as a displacement constraint condition, includes the following steps: At the UAV sampling time , extract the displacement gauge data within the time window from the displacement gauges. Let the extracted displacement gauge data be three-dimensional coordinate points , where n is the number of data points, and the corresponding time points of the data are ; Assume that the time point when the infrared camera obtains the surface identification point data is , and use linear interpolation to obtain the exact aligned displacement gauge coordinates at time point ; ; For each surface identification point Psur(X, Y), assume that its corresponding actual three-dimensional coordinates are (x sur , y sur , z sur ). Establish the projection relationship from the displacement gauge measurement point to the surface identification point Psur(X, Y) through the perspective projection model: ; Among them, is the focal length of the camera, is the coordinate of the displacement gauge measurement point , is the coordinate of the surface identification point Psur; For each pair of mapped points , perform trend consistency test; for the mapping point pairs that pass the trend consistency test, calculate their internal distance and surface distance, determine the weights corresponding to the internal distance and surface distance according to the accuracy of the instrument and the infrared camera carried by the drone, and add the weighted values to obtain the comprehensive displacement. The comprehensive displacements of all the mapping point pairs that pass the trend consistency test are combined into a displacement constraint vector, and a displacement constraint matrix is constructed, which is applied as a displacement constraint condition to the finite element model.

[0010] Furthermore, the finite element model includes the following steps: Obtain the design drawings of the dam, including dimensions, material properties, and structural layout, collect the geological exploration reports of the location where the dam is located, obtain information on foundation soil type, bearing capacity, and groundwater level, and conduct relevant dam material property tests to determine the load conditions, displacement constraint conditions, and boundary conditions of the hydrostatic pressure, sediment pressure, temperature change, and seismic action on the dam; Use professional finite element preprocessing software to establish a three-dimensional geometric model of the dam according to the design drawings. According to the structure and stress characteristics of the dam, select the element type, adjust the mesh size and shape, and use the automatic mesh generation algorithm to mesh the geometric model; According to the actual constraint conditions of the dam, set the symmetric boundary and fixed support boundary conditions, apply the load conditions and displacement constraint conditions to the model, input the material property test results into the model, define the mechanical properties for each material, and use the finite element software to solve the model and output the stress and strain related results; Analyze the stress distribution and strain distribution output by the finite element model. If all indicators are within the normal range, the dam structure is safe; otherwise, the dam structure is abnormal and analysis is carried out.

[0011] Furthermore, the analysis of the stress distribution output by the finite element model includes the following steps: Use professional finite element analysis software to solve the constructed finite element model, calculate the stress value of each node, dynamically adjust its allowable stress threshold according to the mechanical property parameters of the dam material, compare the calculated stress value of each node with its allowable stress threshold, and judge whether there is stress overrun at the node according to the stress ratio value; Stress ratio value calculation formula: ; Where is the stress ratio value of the th node, is the stress value of the th node, is the allowable gradient threshold corresponding to the th node; If It indicates that there is a phenomenon of stress overrun at this node. Conversely, it indicates that there is no stress overrun at this node; Use a graphical tool to draw the stress distribution map of the dam structure, visually display the stress conditions in each area, calculate the stress ratio value of each node, and mark it on the distribution map.

[0012] Furthermore, the analysis of the strain distribution includes the following steps: Extract the strain values of each node from the finite element model. According to the mechanical property parameters of the dam material, determine the maximum allowable strain value. Compare the strain value of each node with the maximum allowable strain value of the material to judge whether there is a strain overrun phenomenon at the node; Use a graphical tool to read the strain values output by the finite element model, draw the strain distribution map of the dam structure, mark the strain values and positions of each area on the map, calculate the ratio of the strain value of each node to the maximum allowable strain value of the material, and mark the ratio value on the strain distribution map. Use the same calculation method as the stress ratio value to obtain the strain ratio value of the th node If

[0013] Furthermore, the abnormal marking construction module includes: Construct abnormal marking rules, including single-index overrun and double-index overrun; Set single-index overrun: If , there is a stress overrun phenomenon at the corresponding node, triggering a yellow warning. If , there is a strain overrun phenomenon at the corresponding node, triggering an orange warning; Set double-index overrun: If and , then there are two overrun phenomena at the corresponding node, triggering a red warning.

[0014] The present invention also provides a method for monitoring and processing dam stability data, including the following steps: S1: Install a variety of special instruments in the internal environment and external environment of the dam to obtain corresponding data; S2: Use a drone equipped with an infrared camera to conduct low-altitude shooting and measurement on the dam and its surrounding environment to obtain image data; S3: Perform preprocessing operations on the displacement gauge data. Set CGC200 as the global standard, arrange identification points and decompose the displacement vector record. After correcting the drone images, identify the identification points, extract the feature vectors, and use the SIFT algorithm to match and determine the displacement; S4: Interpolate and align the displacement gauge data within the time window, establish the projection relationship between the displacement gauge measurement points and the surface identification points, construct a displacement constraint matrix, which is applied as a displacement constraint condition to the finite element model. By obtaining relevant dam data, determine the loads and boundary conditions, and use professional software to construct a finite element model to analyze the stress and strain results; S5: Calculate the corresponding ratio values based on the results of the stress and strain analysis, and construct an abnormal marking rule according to the ratio values.

[0015] Advantages of the present invention: The present invention respectively obtains instrument data and image data through the instrument data acquisition module and the image data acquisition module, and processes and analyzes them, realizing the integration and comprehensive analysis of multi-source data, which helps to more comprehensively understand the deformation of the dam and improve the accuracy and reliability of monitoring; The present invention establishes the projection relationship between the displacement gauge measurement points and the surface identification points through the dam monitoring and analysis module, and constructs a displacement constraint matrix, which is applied as a displacement constraint condition to the finite element model, and then constructs an accurate finite element model of the dam, which can simulate the stress and strain states of the dam under actual working conditions and provide a powerful tool for stability assessment; The present invention constructs ratio values based on the stress and strain results output by the finite element model, and constructs an abnormal marking rule according to the ratio values, which can effectively identify the abnormal areas in the dam structure. Through timely marking and early warning, repair measures can be quickly taken to prevent potential accidents and ensure the safe and stable operation of the dam. Description of the Drawings

[0016] Figure 1 It is a schematic diagram of the module flow of the present invention; Figure 2 It is a schematic diagram of the method flow of the present invention. Detailed Embodiments

[0017] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0018] Please refer to Figure 1 As shown, the present invention is a dam stability data monitoring and processing system, including the following modules: Instrument data acquisition module: Install a variety of special instruments in the internal and external environments of the dam to obtain corresponding data; Image data acquisition module: Use a drone equipped with an infrared camera to take low-altitude photos and measurements of the dam and its surrounding environment to obtain image data; Instrument and image data analysis module: Preprocess the displacement gauge data, set CGC200 as the global standard, lay out identification points and decompose and record the displacement vector. After correcting the drone images, identify the identification points, extract the feature vectors, and use the SIFT algorithm to match and determine the displacement; Dam monitoring and analysis module: Extract and interpolate and align the displacement gauge data within the time window, establish the projection relationship between the displacement gauge measurement points and the surface identification points, construct a displacement constraint matrix, and apply it as a displacement constraint condition to the finite element model. By obtaining relevant information about the dam, determine the loads and boundary conditions, use professional software to construct the finite element model, and analyze the stress and strain results; Abnormal mark construction module: Calculate the corresponding proportional values based on the analysis results of stress and strain, and construct abnormal mark rules according to the proportional values.

[0019] Specifically, according to the dam monitoring requirements and structural characteristics, determine the key parts inside the dam body where displacement gauges, strain gauges, piezometers, and thermometers need to be installed, and determine the key parts outside the dam body where float-type water level gauges and total stations are suitable for installation. Set the data acquisition time interval to once every half hour according to the monitoring requirements, and use full backup to back up the data; Use professional flight planning software or tools, input the parameters of the dam and the mesh division information, generate the flight route of the drone, and take photos of the area with surface identification points set on the surface at the set time interval. After the flight is over, label the image data stored in the camera memory card; Set the dam design coordinate system CGC200 as the global standard coordinate system, obtain the position information of each displacement gauge monitoring point, and use the image recognition algorithm to automatically identify the pre-set surface identification points: The standard template images of the surface identification points can be pre-stored, and then template matching is performed in the images taken by the drone to find the most similar area as the position of the surface identification point; According to the coordinates of the displacement gauge measurement points and the surface identification points, calculate the internal distance and surface distance of each mapping point pair respectively, and determine the weight coefficients of the two according to the accuracy indexes of the displacement gauge and the drone; Determine the design drawings, geological exploration data, load conditions, boundary conditions, and displacement constraint conditions of the dam, and construct a finite element model; Analyze the stress and strain results output by the finite element model, construct stress proportional values and strain proportional values; Construct abnormal warning signals according to the two proportional values.

[0020] In one embodiment of the present invention, the instrument data acquisition module includes: According to the dam monitoring requirements and structural characteristics, install displacement gauges, strain gauges, piezometers, and thermometers at the key parts inside the dam body respectively; install float-type water level gauges and total stations at the key parts outside the dam body respectively; Set the time interval for data acquisition to once every half hour, transmit the data wirelessly to the monitoring center, set up a local server in the monitoring center, and write the acquired data to the local server in real time through the Modbus / TCP protocol. Perform a full backup of the database to the local NAS at 1:00 am every day.

[0021] Specifically, according to the dam monitoring requirements and structural characteristics, determine the key positions inside the dam where displacement gauges, strain gauges, piezometers, and thermometers need to be installed, and determine the key positions outside the dam suitable for installing float-type water level gauges and total station instruments, usually at the upstream and downstream water level observation points of the dam and positions that can comprehensively monitor the deformation of the dam; after all monitoring devices are installed and debugged, set the time interval for data acquisition to once every half hour according to the monitoring requirements, configure a wireless communication module for each monitoring device to ensure that the data it acquires can be transmitted wirelessly to the monitoring center, select a suitable wireless communication protocol and frequency band according to the type and communication requirements of the device, set up a local server in the monitoring center, such as a Windows Server operating system and a MySQL database management system, etc., install software or services that support the Modbus / TCP protocol on the local server, and the server side writes the acquired data to the database of the local server in real time according to the pre-configured Modbus / TCP protocol. Set 1:00 am every day as the time for full backup of the database, use the backup function provided by the database management system or a third-party backup software to create a backup task, set the backup source as the database file on the local server and the backup target as the local NAS (Network Attached Storage) device in the backup task, and specify the backup method as full backup, that is, back up all the data of the entire database each time.

[0022] In one embodiment of the present invention, the image data acquisition module includes: Conduct a comprehensive survey of the dam and its surrounding environment to determine the takeoff and landing points of the unmanned aerial vehicle; combine the shape, size, and key monitoring parts of the dam, and use a grid-based flight route planning method to determine the flight parameters of the unmanned aerial vehicle, including flight altitude, speed, and heading; The operator controls the unmanned aerial vehicle to fly according to the planned flight route, monitors the flight state of the unmanned aerial vehicle and the imaging situation of the infrared camera in real time through the video transmission system, takes pictures of the area with surface marking points every half hour at the set time interval to obtain the image data of the dam surface. After the flight is over, label the image data stored in the camera memory card, including the shooting time, location, and shooting angle; use the same storage and backup method as in the instrument data acquisition module, and perform denoising and image enhancement processing.

[0023] Specifically, organize professional personnel to conduct a comprehensive survey of the dam and its surrounding environment, understand the terrain, obstacle distribution, electromagnetic environment, etc., mark the positions suitable for UAV takeoff and landing, select several ideal takeoff and landing point positions according to the survey results, record their geographical coordinates and relevant characteristics, test the selected takeoff and landing points to ensure that the UAV can take off and land safely; obtain the detailed design drawings or measured data of the dam, including geometric parameters such as the length, width, and height of the dam, analyze the structure of the dam and the key monitoring parts, such as the dam body, slope protection, spillway, etc., divide the surface of the dam into several grid areas according to the shape and size of the dam to ensure that each area can be covered by the UAV, determine the size of the grid and the spacing of the flight route according to the flight performance of the UAV and the viewing angle range of the camera, use professional flight planning software or tools, input the parameters of the dam and the grid division information, and generate the flight route of the UAV; determine the flight parameters such as flight altitude, speed, and heading according to the flight route and the performance characteristics of the UAV, and during the flight, monitor the flight state of the UAV in real time through the video transmission system, including information such as position, altitude, and speed. At the same time, monitor the imaging situation of the infrared camera, and take pictures of the areas with surface marking points at set time intervals. After the flight, annotate the image data stored in the camera memory card.

[0024] In one embodiment of the present invention, the instrument and image data analysis module includes: Perform data cleaning and data conversion operations on the raw data collected by the displacement meter; set the dam design coordinate system CGC200 as the global standard, and arrange at least 4 permanent surface marking points on the dam surface; Determine the relationship between each direction of each displacement meter monitoring point and the coordinate axes, decompose the total displacement vector into each coordinate axis direction according to the vector decomposition principle, and calculate the magnitude and direction of the displacement components of each monitoring point in different directions according to the decomposition principle and the determined coordinate system; create a data record table for each monitoring point, and record the displacement values in the x, y, and z directions and the corresponding timestamps respectively; Perform geometric correction and radiometric correction on the images taken by the UAV, use image recognition algorithms to automatically identify the pre-set surface marking points in the corrected images, and use feature extraction algorithms to extract the central coordinates, gray-scale features, and texture features of the surface marking points as the image feature vectors of the surface marking points; according to the feature vectors of the surface marking points in the images of different time series, use the SIFT-based matching algorithm to determine the position changes of the surface marking points in the images taken before and after, and calculate the displacement data of the dam surface.

[0025] Specifically, set the dam design coordinate system CGC200 as the global standard coordinate system, obtain the position information of each displacement gauge monitoring point, including the specific position and spatial orientation on the dam surface, and determine the relationship between each direction and the coordinate axes at each monitoring point according to the structure of the dam and the layout of the monitoring points. For example, for a horizontally arranged displacement gauge, its measurement direction may be parallel to the x-axis or y-axis of the coordinate axes; for a vertically arranged displacement gauge, the measurement direction is consistent with the z-axis direction. According to the vector decomposition principle, decompose the total displacement vector into each coordinate axis direction. According to the determined coordinate relationship and decomposition principle, calculate the magnitude of the displacement components of each monitoring point in different directions. For example, if the angle between the total displacement vector and the x-axis is θ and the displacement magnitude is D, the displacement component in the x-direction is D×cosθ. Create a data record table for each monitoring point, and the table content includes the time stamp, the displacement value in the x-direction, the displacement value in the y-direction, and the displacement value in the z-direction. In the corrected image, first perform image preprocessing operations to improve the accuracy of image recognition. Use image recognition algorithms to automatically identify the pre-set surface identification points: the standard template image of the surface identification points can be pre-stored, and then template matching is performed in the images taken by the drone to find the most similar area as the position of the surface identification points. Use feature extraction algorithms to extract the center coordinates, gray-scale features, and texture features of the surface identification points as the image feature vectors of the surface identification points. The SIFT algorithm finds the corresponding surface identification points in different images by comparing the similarity of the feature vectors and calculates the position offset between them, converts the position offset into the actual displacement value, and determines the direction of the displacement.

[0026] In one embodiment of the present invention, the construction of the displacement constraint matrix, which is applied to the finite element model as a displacement constraint condition, includes the following steps: For the sampling time of the drone , extract the displacement gauge data within the time window from the displacement gauge. Let the extracted displacement gauge data be three-dimensional coordinate points , where n is the number of data points, and the time point corresponding to the data is ; Assume that the time point when the infrared camera obtains the surface identification point data is , and use linear interpolation to obtain the precise alignment displacement gauge coordinates at the time point ; ; For each surface identification point Psur(X, Y), assume that its corresponding actual three-dimensional coordinates are (x sur , y sur , z sur ). Establish the projection relationship from the displacement gauge measurement point to the surface identification point Psur(X, Y) through the perspective projection model: ; wherein, is the focal length of the camera, is the coordinate of the displacement gauge measurement point ; is the coordinate of the surface identification point Psur; For each pair of mapped points , a trend consistency test is performed; for the pairs of mapped points that pass the trend consistency test, calculate their internal distance and surface distance, determine the weights corresponding to the internal distance and surface distance according to the accuracy of the instrument and the infrared camera carried by the drone, add the weighted values to obtain the comprehensive displacement, form a displacement constraint vector with the comprehensive displacements of all pairs of mapped points that pass the trend consistency test, and construct a displacement constraint matrix, which is applied as a displacement constraint condition to the finite element model.

[0027] Specifically, for each pair of mapped points ; calculate the direction vector from the displacement gauge measurement point to the surface identification point and the cosine value of the included angle between the direction vectors of all pairs of mapped points and the z-axis direction vector, compare the cosine value of the included angle with a preset threshold. If the cosine value of the included angle is greater than the preset threshold, the trend of this pair of mapped points is consistent with the reference direction and passes the test; otherwise, it fails the test; wherein, the preset threshold is set to μ - 2σ, and μ is the mean value of the cosine values of the included angles measured multiple times, which can exclude the deviation caused by measurement errors to a certain extent; for the pairs of mapped points that pass the trend consistency test, calculate their internal distance and surface distance, determine the weights corresponding to the internal distance and surface distance according to the accuracy of the instrument and the infrared camera carried by the drone, add the weighted values to obtain the comprehensive displacement, form a displacement constraint vector with the comprehensive displacements of all pairs of mapped points that pass the trend consistency test, according to the node degrees of freedom of the finite element model and the corresponding relationship between the mapped points and the nodes, and construct a displacement constraint matrix. Each row of the matrix corresponds to a pair of mapped points, and each column corresponds to the degree of freedom of a node. If there is a corresponding relationship between the mapped point and the node, the element at this position is 1, otherwise it is 0; apply it as a displacement constraint condition to the finite element model; The internal distance, that is, the distance from the displacement gauge measurement point to the surface identification point Psur in the actual three-dimensional space, is obtained through: ; to obtain as the internal distance of this point, and are the three-dimensional coordinates of Psur and respectively; The surface distance, that is, the two-dimensional image distance from the projection point of the displacement gauge measurement point on the image plane to the surface identification point; Determine the weights corresponding to the internal distance and the surface distance according to the accuracies of the instrument and the infrared camera mounted on the drone, that is, unify the units of the displacement gauge accuracy and the camera positioning accuracy and then add them to obtain the comprehensive accuracy, divide the displacement gauge accuracy and the camera positioning accuracy by the comprehensive accuracy respectively to obtain the corresponding accuracy ratio values, which are used as their corresponding weights.

[0028] In one embodiment of the present invention, the finite element model includes the following steps: Obtain the design drawings of the dam, including dimensions, material properties and structural layout, collect the geological exploration reports of the location where the dam is located, obtain the information of the foundation soil type, bearing capacity and groundwater level, and conduct relevant dam material property tests to determine the load conditions, displacement constraint conditions and boundary conditions of the hydrostatic pressure, sediment pressure, temperature change and seismic action suffered by the dam; Use professional finite element preprocessing software to establish a three-dimensional geometric model of the dam according to the design drawings, select the element type according to the structure and stress characteristics of the dam, adjust the mesh size and shape, and use the automatic mesh generation algorithm to divide the mesh of the geometric model; According to the actual constraint conditions of the dam, set the symmetric boundary and fixed support boundary conditions, apply the load conditions and displacement constraint conditions to the model, input the material property test results into the model, define the mechanical properties for each material, and use the finite element software to solve the model and output the stress and strain related results; Analyze the stress distribution and strain distribution output by the finite element model. If all indicators are within the normal range, the dam structure is safe; otherwise, the dam structure is abnormal and analysis is carried out.

[0029] Specifically, contact the dam construction, design or management unit, and obtain the design drawings of the dam through formal applications, communication and coordination, etc. Conduct a detailed check on the obtained design drawings, apply for obtaining the geological exploration report, and sort out the report content. Collect representative material samples at different parts of the dam. For concrete materials, drill holes for sampling at different pouring parts; for earth-rock materials, select undisturbed soil samples or rock samples at different depths and positions of the dam body. Determine the material property test items to be carried out according to the material type and the dam structure characteristics, such as the compressive strength, elastic modulus, and impermeability of concrete, and the compression modulus, internal friction angle, cohesion, etc. of earth-rock materials. Send the collected samples to a professional material laboratory, and use corresponding instruments and equipment to conduct material property tests according to standard test methods, and record the test results; According to the information such as the design shape, size and water level elevation of the dam, use the principles of fluid mechanics to calculate the distribution of hydrostatic pressure on the dam. Consider factors such as the sediment characteristics and water flow velocity of the river where the dam is located, estimate the thickness and scope of the sediment deposited upstream of the dam, and then calculate the horizontal pressure generated by the sediment on the dam. Collect historical meteorological data such as air temperature and water temperature and real-time monitoring data in the area where the dam is located, and determine the thermal stress generated by temperature changes on the dam. According to the seismic activity situation and seismic fortification requirements in the area where the dam is located, use the seismic hazard analysis method to determine the possible seismic parameters; Import the design drawings of the dam into a professional finite element preprocessing software in a suitable file format, automatically identify the outlines and sizes of each part of the dam according to the imported drawing information, and use the automatic mesh generation algorithm provided by the software to mesh the geometric model; Implement the symmetric boundary setting by specifying the node degree-of-freedom constraints on the symmetric plane. According to the actual support situation of the dam, apply the fixed support boundary conditions to the corresponding nodes. Input the previously calculated load conditions such as hydrostatic pressure, sediment pressure, thermal stress generated by temperature changes, and seismic action into the model in a suitable way. Apply the determined displacement constraint conditions to the specified nodes or regions of the model. According to the material property test results, define the mechanical property parameters for each material in the finite element model; Select a suitable solver in the finite element software, such as the direct solution method, the iterative solution method, etc., and make corresponding solver settings according to the scale and nature of the problem. Set the result types and formats to be output before solving. In one embodiment of the present invention, the analysis based on the stress distribution output by the finite element model includes the following steps: Use professional finite element analysis software to solve the constructed finite element model, calculate the stress values of each node, dynamically adjust its allowable stress threshold according to the mechanical property parameters of the dam material, compare the calculated stress value of each node with its allowable stress threshold, and judge whether there is a stress overrun phenomenon at the node according to the stress ratio value; Stress ratio value calculation formula: ; wherein, is the stress ratio value of the -th node, is the stress value of the -th node, is the allowable gradient threshold corresponding to the -th node; If , it indicates that there is a phenomenon of excessive stress at this node, otherwise, it indicates that there is no phenomenon of excessive stress at this node; Use a graphical tool to draw the stress distribution map of the dam structure, visually display the stress conditions of each area, calculate the stress ratio value of each node, and mark it on the distribution map.

[0030] Specifically, look up the mechanical property parameters of different materials, such as concrete, earth-rock, etc., including elastic modulus, Poisson's ratio, compressive strength, tensile strength, etc. in the dam design data or relevant specifications. These parameters are the basis for determining the allowable stress threshold. Considering the actual working conditions of the dam, such as water level change, temperature change, seismic action, etc., determine the corresponding adjustment coefficients for different working conditions and different parts of the dam. For example, when the water level is high, due to the buoyancy and pressure of water, for the dam materials in the underwater part, the allowable stress threshold may need to be appropriately reduced. Through the secondary development function of the software, according to the above-obtained material mechanical property parameters and adjustment coefficients, calculate the allowable stress threshold of each node under different working conditions; use data processing software to divide the extracted node stress value by the corresponding allowable stress threshold to obtain the stress ratio value of each node, and judge whether there is a phenomenon of excessive stress at each node. In the post-processing module of the finite element analysis software, select "Plot Results" or a similar function, select an appropriate plotting method to draw the stress distribution map of the dam structure, and use the annotation function or graphic editing tool of the software to mark the stress ratio value of each node on the stress distribution map.

[0031] An example table for determining excessive dam stress is shown in Table 1: Table 1.

[0032] In one embodiment of the present invention, the analysis of the strain distribution includes the following steps: Extract the strain values of each node from the finite element model, determine the maximum allowable strain value according to the mechanical property parameters of the dam material, compare the strain value of each node with the maximum allowable strain value of the material, and judge whether there is a phenomenon of excessive strain at the node; Use a graphical tool to read the strain values output from the finite element model and draw the strain distribution map of the dam structure. Mark the strain values and positions of each area on the map, calculate the ratio of the strain value of each node to the maximum allowable strain value of the material, and mark the ratio value on the strain distribution map. Use the same calculation method as the stress ratio value to obtain the strain ratio value of the th node . If , it indicates that there is a strain overrun phenomenon at this node. Otherwise, it indicates that there is no strain overrun phenomenon at this node.

[0033] Specifically, open the finite element analysis software. After completing the model solution, enter the post-processing module of the software. Directly click on a single node on the model with the mouse, or use the node selection tool provided by the software to select nodes, and output the strain values of the selected nodes to a text file, a table file, or a specific data structure inside the software for subsequent operations; consult the mechanical property data of various materials used in the dam design and construction, calculate the maximum allowable strain values of each material under different working conditions according to the mechanical property parameters of the materials, and organize the calculated maximum allowable strain values in a way that aligns with the node table to form a format corresponding to the node strain value data; compare the extracted node strain value data with the sorted maximum allowable strain value data one by one, calculate the strain ratio value of each node, and determine whether there is a strain overrun phenomenon at the node according to the strain ratio value; in the graphical tool, draw the strain distribution map of the dam structure according to the imported node strain value data, and mark the strain ratio value and position information of each node on the strain distribution map.

[0034] The implementation example table for determining the dam strain overrun is shown in Table 2 as follows: Table 2.

[0035] In one embodiment of the present invention, the abnormal marking construction module includes: Construct abnormal marking rules, including single-index overrun and double-index overrun; Set single-index overrun: If , there is a stress overrun phenomenon at the corresponding node, triggering a yellow warning. If , there is a strain overrun phenomenon at the corresponding node, triggering an orange warning; Set double-index overrun: If and , then there are two overrun phenomena at the corresponding node, triggering a red warning.

[0036] Specifically, defining the single-index overrun rule includes clarifying the evaluation criteria for stress and strain respectively. For stress, when the stress ratio value of a node is greater than 1, it is determined that the stress is overrunning; for strain, when the strain ratio value of a node is greater than 1, it is determined that the strain is overrunning; and determining the corresponding relationship between the warning color and the overrun type. When stress overrun occurs, a yellow warning is triggered; when strain overrun occurs, an orange warning is triggered. Defining the double-index overrun rule includes stipulating that when both the stress ratio value and the strain ratio value of the same node are greater than 1, it is determined that there are two overrun phenomena at this node, that is, double-index overrun, and determining that a red warning is triggered when double-index overrun occurs to highlight this more serious abnormal situation.

[0037] Please refer to Figure 2 As shown, the present invention is a method for monitoring and processing dam stability data, including the following steps: S1: Install a variety of special instruments in the internal environment and external environment of the dam to obtain corresponding data; S2: Use a drone equipped with an infrared camera to conduct low-altitude shooting and measurement of the dam and its surrounding environment to obtain image data; S3: Perform preprocessing operations on the displacement meter data, set CGC200 as the global standard, lay out identification points and decompose the displacement vector record, identify the identification points after correcting the drone image, extract the feature vector, and use the SIFT algorithm to match and determine the displacement; S4: Extract and interpolate and align the displacement meter data within the time window, establish the projection relationship between the displacement meter measurement points and the surface identification points, construct a displacement constraint matrix, which is applied as a displacement constraint condition to the finite element model, determine the load and boundary conditions by obtaining relevant dam information, use professional software to construct the finite element model, and analyze the stress and strain results; S5: Calculate the corresponding ratio value based on the analysis results of stress and strain, and construct an abnormal marking rule according to the ratio value.

[0038] The above embodiments are only used to illustrate the technical method of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical method of the present invention can be modified or equivalently replaced without departing from the spirit and scope of the technical method of the present invention.

Claims

1. A dam stability data monitoring and processing system, characterized in that: Includes the following modules: Instrument data acquisition module: a variety of special instruments are installed in the internal and external environments of the dam to obtain corresponding data; Image data acquisition module: Use a drone equipped with an infrared camera to take low-altitude photos and measurements of the dam and its surrounding environment to obtain image data; Instrument and image data analysis module: pre-process the displacement meter data, set CGC200 as the global standard, lay out the identification points and decompose the displacement vector records, identify the identification points after correcting the UAV image, extract the feature vector, and use the SIFT algorithm to match and determine the displacement; Dam monitoring and analysis module: extract the displacement meter data within the time window, interpolate and align them, establish the projection relationship between the displacement meter measurement points and the surface identification points, construct the displacement constraint matrix, which is applied to the finite element model as a displacement constraint condition, obtain relevant dam data, determine the load and boundary conditions, use professional software to build the finite element model, and analyze the stress and strain results; Abnormal marking construction module: Calculate the corresponding proportion value by analyzing the results of stress and strain, and construct abnormal marking rules according to the proportion value.

2. A dam stability data monitoring and processing system according to claim 1, characterized in that: The instrument data acquisition module comprises: According to the monitoring requirements and structural characteristics of the dam, displacement meters, strain gauges, piezometers and thermometers are installed at key locations inside the dam body; float-type water level gauges and total stations are installed at key locations outside the dam body; The data collection time interval is set to collect data every half hour, and wireless communication is used to transmit data to the monitoring center. A local server is set up in the monitoring center, and the acquired data is written to the local server in real time through the Modbus / TCP protocol. The database is fully backed up to the local NAS at 1 a.m. every day.

3. A dam stability data monitoring and processing system according to claim 1, characterized in that: The image data acquisition module comprises: Conduct a comprehensive survey of the dam and its surrounding environment to determine the take-off and landing points of the drone; use a grid-based flight route planning method based on the shape, size and key monitoring areas of the dam to determine the flight parameters of the drone, including flight altitude, speed and heading; The operator controls the UAV to fly according to the planned flight route, monitors the flight status of the UAV and the imaging of the infrared camera in real time through the image transmission system, and takes pictures of the area with surface marking points every half an hour at the set time interval to obtain image data of the dam surface. After the flight, the image data stored in the camera memory card is annotated, including the time, location and shooting angle of the shooting; the same storage and backup method as in the instrument data acquisition module is used, and denoising and image enhancement processing are performed.

4. A dam stability data monitoring and processing system according to claim 1, characterized in that: The instrument and image data analysis module include: Perform data cleaning and data conversion operations on the raw data collected by the displacement meter; set the dam design coordinate system CGC200 as the global standard, and set at least 4 permanent surface identification points on the dam surface; Determine the relationship between each direction and the coordinate axis at each displacement meter monitoring point, decompose the total displacement vector into the directions of each coordinate axis according to the vector decomposition principle, and calculate the size and direction of the displacement components of each monitoring point in different directions according to the decomposition principle and the determined coordinate system; create a data record table for each monitoring point, and record its displacement values ​​in the x, y and z directions and the corresponding timestamps respectively; The images taken by the drone are subjected to geometric correction and radiation correction. The image recognition algorithm is used to automatically identify the pre-set surface identification points in the corrected images. The feature extraction algorithm is used to extract the center coordinates, grayscale features and texture features of the surface identification points as the image feature vectors of the surface identification points. According to the feature vectors of the surface identification points in images of different time series, the SIFT-based matching algorithm is used to determine the position changes of the surface identification points in the two images taken before and after, and calculate the displacement data of the dam surface.

5. A dam stability data monitoring and processing system according to claim 1, characterized in that: The construction of the displacement constraint matrix, which is applied to the finite element model as a displacement constraint condition, includes the following steps: Sampling time of drone , extract the displacement meter data within the time window from the displacement meter, and assume that the extracted displacement meter data is the three-dimensional coordinate point , where n is the number of data points and the time point corresponding to the data is ; Assume that the time point at which the infrared camera obtains the surface marker data is , use linear interpolation to get the time point Precise alignment of displacement gauge coordinates ; For each surface marker point Psur (X, Y), assume that its corresponding actual three-dimensional coordinates are (x sur ,y sur , z sur ), establish displacement measurement points through perspective projection model The projection relationship to the surface identification point Psur (X, Y): ； in, is the focal length of the camera, Displacement measuring point The coordinates of is the coordinate of the surface marker point Psur; For each mapping point pair , perform trend consistency test; for the mapping point pairs that pass the trend consistency test, calculate their internal distance and surface distance, determine the weights corresponding to the internal distance and surface distance according to the accuracy of the instrument and the infrared camera carried by the UAV, and add the weighted displacement to get the comprehensive displacement. The comprehensive displacement of all mapping point pairs that pass the trend consistency test is composed into a displacement constraint vector, and a displacement constraint matrix is ​​constructed, which is applied to the finite element model as a displacement constraint condition.

6. A dam stability data monitoring and processing system according to claim 5, characterized in that: The finite element model comprises the following steps: Obtain the design drawings of the dam, including dimensions, material properties and structural layout, collect the site survey report of the dam location, obtain the foundation soil type, bearing capacity and groundwater level information, and conduct relevant dam material property tests to determine the load conditions, displacement constraints and boundary conditions of the dam under hydrostatic pressure, sediment pressure, temperature changes and seismic effects; Use professional finite element pre-processing software to build a 3D geometric model of the dam based on the design drawings. Select the unit type based on the structure and stress characteristics of the dam, adjust the mesh size and shape, and use the automatic mesh production algorithm to mesh the geometric model. According to the actual constraints of the dam, symmetric boundary and fixed support boundary conditions are set, load conditions and displacement constraints are applied to the model, material property test results are input into the model, mechanical properties are defined for each material, the model is solved using finite element software, and stress and strain related results are output; According to the stress distribution output by the finite element model, the strain distribution is analyzed. If all indicators are within the normal range, the dam structure is safe. Otherwise, the dam structure is abnormal and further analysis is conducted.

7. A dam stability data monitoring and processing system according to claim 6, characterized in that: The analysis based on the stress distribution output by the finite element model includes the following steps: Use professional finite element analysis software to solve the constructed finite element model, calculate the stress value of each node, dynamically adjust its allowable stress threshold according to the mechanical performance parameters of the dam material, compare the calculated stress value of each node with its allowable stress threshold, and judge whether the node has stress overlimit phenomenon according to the stress ratio value; Stress ratio calculation formula: ； in, For the The stress ratio value of each node is For the The stress value of each node, For the The allowed gradient threshold corresponding to each node; like , it means that there is stress over limit phenomenon at the node, otherwise, it means that there is no stress over limit phenomenon at the node; Use graphical tools to draw the stress distribution diagram of the dam structure, intuitively display the stress conditions in each area, calculate the stress ratio value of each node, and mark it on the distribution diagram.

8. A dam stability data monitoring and processing system according to claim 6, characterized in that: The analysis of strain distribution comprises the following steps: Extract the strain value of each node from the finite element model, determine the maximum allowable strain value based on the mechanical properties of the dam material, compare the strain value of each node with the maximum allowable strain value of the material, and determine whether the node has strain exceeding the limit; Use a graphical tool to read the strain value output by the finite element model and draw a strain distribution diagram of the dam structure. Mark the strain value and position of each area in the diagram. Calculate the ratio of the strain value of each node to the maximum strain value allowed by the material, and mark the ratio value on the strain distribution diagram. Use the same calculation method as the stress ratio value to obtain the first Strain ratio value of each node ,like , it means that there is an over-strain phenomenon at the node, otherwise, it means that there is no over-strain phenomenon at the node.

9. A dam stability data monitoring and processing system according to claim 1, characterized in that: The abnormal marking construction module includes: Construct abnormal marking rules, including single-indicator over-limit and double-indicator over-limit; Set single indicator over limit: If , the corresponding node has stress exceeding the limit, triggering a yellow warning. , the corresponding node has strain exceeding the limit, triggering an orange warning; Set double index over limit: If and , there are two over-limit phenomena at the corresponding node, triggering a red warning.

10. A dam stability data monitoring and processing method, using a dam stability data monitoring and processing system according to any one of claims 1 to 9, characterized in that: The following steps are involved: S1: Install a variety of special instruments in the internal and external environments of the dam to obtain corresponding data; S2: Use a drone equipped with an infrared camera to take low-altitude photos and measurements of the dam and its surrounding environment to obtain image data; S3: Preprocess the displacement meter data, set CGC200 as the global standard, lay out the marker points and decompose the displacement vector records, identify the marker points after correcting the drone image, Extract feature vectors and use SIFT algorithm to match and determine displacement; S4: Extract the displacement meter data within the time window, interpolate and align them, establish the projection relationship between the displacement meter measurement points and the surface identification points, determine the weights based on the equipment accuracy to calculate the comprehensive displacement, and input it into the finite element model as part of the boundary conditions. By obtaining relevant information about the dam, determine the load and boundary conditions, use professional software to build a finite element model, and analyze the stress and strain results; S5: Calculate the corresponding ratio value by analyzing the stress and strain results, and construct an abnormal marking rule according to the ratio value.

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