Method and system for constructing three-dimensional visual model of mine slope

Abstract

The invention provides a three-dimensional visual model construction method and system for a mine slope, and relates to the technical field of data processing, and the method comprises the steps: obtaining the inclined image data of the mine slope; performing error correction on the inclined image data; performing live-action modeling according to the inclined image data after error correction to obtain a three-dimensional grid model and a point cloud data file; generating a digital terrain model according to the point cloud data file; extracting a contour line of the digital terrain model, and exporting a contour line file; generating a three-dimensional terrain curved surface by using a terrain data generator according to the contour line file; the three-dimensional terrain curved surface extends downwards by a preset depth, and a three-dimensional entity slope model is generated; physical parameters of side slope rock soil are set, and a Moire-Coulomb intensity criterion is given to the three-dimensional entity side slope model so as to simulate shear failure characteristics of the rock soil; on the basis of shear failure characteristics of rock and soil, grid division is carried out on the three-dimensional solid slope model; and generating a three-dimensional visual model of the mine slope.

Description

Technical Field

[0001] The present invention relates to the technical field of data processing, and particularly to a method and system for constructing a three-dimensional visualization model of a mine slope. Background Art

[0002] The stability of a mine slope is one of the key safety issues in the process of mineral resource exploitation. The instability of the slope may lead to serious economic losses and safety accidents, and also have an adverse impact on the environmental protection of the mine. The construction of a three-dimensional visualization model can intuitively display the geometric shape, internal structure and stress distribution state of the mine slope, providing an important basis for scientifically evaluating the slope stability, optimizing the design and early warning monitoring.

[0003] Currently, the three-dimensional modeling technology of mine slopes mainly relies on three methods: traditional surveying and mapping methods, remote sensing technologies (including LiDAR, UAV photogrammetry, etc.) and numerical simulation methods based on geological software. These technologies are widely used in mine geological surveys and stability assessments by collecting terrain data, analyzing slope structures and constructing virtual three-dimensional models.

[0004] However, the existing technologies are not accurate enough in the error correction of oblique image data, resulting in deviations in the basic model data and affecting the overall accuracy of subsequent three-dimensional grid models and point cloud data. In the mesh generation of three-dimensional solid slope models, dynamic optimization according to rock layer characteristics fails to be carried out, resulting in low computational efficiency and insufficient local accuracy, making it difficult to comprehensively reflect the actual characteristics of the slope. Summary of the Invention

[0005] In order to solve the technical problems that the existing technologies are not accurate enough in the error correction of oblique image data, resulting in deviations in the basic model data and affecting the overall accuracy of subsequent three-dimensional grid models and point cloud data, and in the mesh generation of three-dimensional solid slope models, dynamic optimization according to rock layer characteristics fails to be carried out, resulting in low computational efficiency and insufficient local accuracy, making it difficult to comprehensively reflect the actual characteristics of the slope, the present invention provides a method and system for constructing a three-dimensional visualization model of a mine slope.

[0006] The technical solutions provided by the embodiments of the present invention are as follows:

[0007] First aspect:

[0008] A method for constructing a three-dimensional visualization model of a mine slope provided by an embodiment of the present invention includes:

[0009] S1: Obtain the oblique image data of the mine slope;

[0010] S2: Perform error correction on the oblique image data;

[0011] S3: Based on the error-corrected tilted image data, perform real-scene modeling to obtain a three-dimensional mesh model and a point cloud data file;

[0012] S4: Generate a digital terrain model according to the point cloud data file;

[0013] S5: Extract the contour lines of the digital terrain model and export the contour line file;

[0014] S6: According to the contour line file, use a terrain data generator to generate a three-dimensional terrain surface;

[0015] S7: Extend the three-dimensional terrain surface downward by a preset depth to generate a three-dimensional solid slope model;

[0016] S8: Set the physical parameters of the slope rock and soil, and endow the three-dimensional solid slope model with the Mohr-Coulomb strength criterion to simulate the shear failure characteristics of the rock and soil;

[0017] S9: Based on the shear failure characteristics of the rock and soil, perform mesh division on the three-dimensional solid slope model;

[0018] S10: Generate a three-dimensional visualization model of the mine slope according to the mesh division result.

[0019] Second aspect:

[0020] A three-dimensional visualization model construction system for a mine slope provided by an embodiment of the present invention includes:

[0021] A processor;

[0022] A memory, on which computer-readable instructions are stored. When the computer-readable instructions are executed by the processor, the method for constructing a three-dimensional visualization model of a mine slope as described in the first aspect is implemented.

[0023] Third aspect:

[0024] A computer-readable storage medium provided by an embodiment of the present invention, on which a computer program is stored. When the program is executed by a processor, the method for constructing a three-dimensional visualization model of a mine slope as described in the first aspect is implemented.

[0025] The beneficial effects brought by the technical solution provided by the embodiment of the present invention at least include:

[0026] (1) In the present invention, by performing error correction on the tilted image data and performing real-scene modeling on the basis of the error correction to generate a high-precision three-dimensional mesh model and a point cloud data file, the problem of model distortion caused by data deviation is effectively avoided. Further, a digital terrain model is generated using the point cloud data to ensure that the basic terrain data of the three-dimensional model is more accurate, thereby improving the accuracy and reliability of the overall model.

[0027] (2) In the present invention, by setting the physical parameters of the slope rock and soil and endowing the three-dimensional solid slope model with the Mohr-Coulomb strength criterion to simulate the shear failure characteristics of the rock and soil, the three-dimensional solid slope model is meshed according to the characteristics of the rock and soil, realizing the dynamic optimization meshing of different rock strata, improving the accuracy of meshing, and further improving the accuracy and reliability of the three-dimensional visualization model of the mine slope. Description of the Drawings

[0028] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0029] Figure 1 It is a schematic flow chart of a method for constructing a three-dimensional visualization model of a mine slope provided by an embodiment of the present invention;

[0030] Figure 2 It is a schematic structural diagram of a system for constructing a three-dimensional visualization model of a mine slope provided by an embodiment of the present invention. Detailed Embodiments

[0031] The following will describe the technical solutions in the present invention with reference to the drawings.

[0032] In the embodiments of the present invention, words such as "exemplarily" and "for example" are used to represent examples, illustrations or explanations. Any embodiment or design solution described as an "example" in the present invention should not be construed as being more preferred or having more advantages than other embodiments or design solutions. Exactly speaking, the use of the word "example" is intended to present concepts in a specific manner. In addition, in the embodiments of the present invention, the meaning expressed by "and / or" can be both, or either one of the two.

[0033] In the embodiments of the present invention, "image" and "picture" can sometimes be used interchangeably. It should be noted that when the difference is not emphasized, the meanings they express are the same. "(of)", "corresponding", and "corresponding" can sometimes be used interchangeably. It should be noted that when the difference is not emphasized, the meanings they express are the same.

[0034] In the embodiments of the present invention, sometimes subscripts such as W1 may be written in a non-subscript form such as W1. When the difference is not emphasized, the meanings they express are the same.

[0035] To make the technical problems, technical solutions, and advantages to be solved by the present invention clearer, the following will be described in detail with reference to the accompanying drawings and specific embodiments.

[0036] Refer to the attached Figure 1 of the specification, which shows a schematic flow chart of a method for constructing a three-dimensional visualization model of a mine slope provided by an embodiment of the present invention.

[0037] An embodiment of the present invention provides a method for constructing a three-dimensional visualization model of a mine slope. This method can be implemented by a device for constructing a three-dimensional visualization model of a mine slope, and this device for constructing a three-dimensional visualization model of a mine slope can be a terminal or a server. The processing flow of the method for constructing a three-dimensional visualization model of a mine slope can include the following steps:

[0038] S1: Obtain the inclined image data of the mine slope.

[0039] Optionally, the step of obtaining the inclined image data of the mine slope includes:

[0040] Determine that the mine slope is the flight area of the unmanned aerial vehicle.

[0041] Conduct fixed-point exploration on the flight area to obtain the fixed-point exploration result.

[0042] According to the fixed-point exploration result, determine the flight path, flight altitude, and preliminary layout position of the image control points of the unmanned aerial vehicle.

[0043] Use the RTK-GNSS technology to measure the preliminary layout position of the image control points and determine the precise layout position of the image control points.

[0044] Among them, RTK (Real-Time Kinematic) technology is a method for high-precision positioning using the Global Navigation Satellite System (GNSS). RTK-GNSS corrects the GNSS satellite positioning error in real time through differential technology, thereby achieving centimeter-level or even sub-centimeter-level positioning accuracy.

[0045] According to the determined flight path, set the overlap degree threshold of the images for the same shooting area during the aerial photography of the unmanned aerial vehicle.

[0046] According to the flight path and the flight altitude, set the flight parameters of the unmanned aerial vehicle.

[0047] Execute the flight operation of the unmanned aerial vehicle according to the flight parameters, and collect the inclined image data of the mine slope based on the precise layout position of the image control points and the overlap degree threshold of the images.

[0048] In the present invention, the RTK-GNSS technology is used to determine the precise positions of image control points, which can significantly improve the positioning accuracy of the image control points, thereby providing high-precision basic data for subsequent oblique image error correction and 3D modeling. At the same time, the precise arrangement of image control points and reasonable flight parameters ensure that the collected image data has high resolution, high coverage, and low distortion, providing a solid foundation for generating high-quality 3D models in the future.

[0049] S2: Perform error correction on the oblique image data.

[0050] In a possible implementation manner, S2 specifically includes:

[0051] Correct the distortion error of the oblique image data.

[0052] In the present invention, by correcting the distortion errors (such as radial distortion and decentering distortion) in the UAV oblique images, the errors caused by non-measurement camera lenses can be significantly reduced, ensuring that the image data meets the accuracy requirements of 3D modeling.

[0053] Correct the exterior orientation element errors caused by the UAV flight attitude deviation in oblique photography.

[0054] Specifically, the process of correcting the exterior orientation element errors is as follows: during low-altitude UAV photography, the coordinate and attitude information of the image. During the imaging process of aerial surveying, if the UAV deviates from its original orientation due to certain reasons, the ground object coordinates will change, and the resulting error can be expressed as:

[0055]

[0056] In the formula: f is the camera focal length, x and y are the image coordinates of the target point, X, Y, and Z represent the low-altitude ground coordinates, X s , Y s , Z s —the ground coordinates of the camera, a ij is the rotation element determined by the exterior orientation angle elements ω, k.

[0057] Perform linearization calculation on the above formula. Since the UAV is in an approximately vertical state during the measurement process, the exterior orientation angle element coordinates are approximately zero, that is, not considered. Taking ω, k as variables, the expressions for the influence on x and y of the image can be obtained:

[0058]

[0059] According to the above formula: dX s , dY s , dZ sThe dk has an impact on the image, causing a certain degree of translation, rotation, and scaling in the entire part of the image. However, since the overall change is linear, only and dω cause non - linear distortion to the image.

[0060] In the present invention, the errors of the exterior orientation elements caused by the attitude deviation of the unmanned aerial vehicle during flight are corrected to ensure that the spatial position and angular information of the image are more accurate, and the matching accuracy between the image and the actual geographical location is enhanced.

[0061] By shortening the exposure time and using the image motion compensation technology, the displacement error of the image is corrected.

[0062] In the present invention, by shortening the exposure time and adopting the image motion compensation technology, the displacement error of the image is corrected, effectively eliminating the blurring and trailing effects caused by vibrations and camera swings during flight, and improving the image clarity.

[0063] By accurately measuring the image control points, the coordinate error of the control points is corrected.

[0064] The marked position of the control points in the image and the piercing point error caused by complex terrain or blurred markings are corrected.

[0065] It should be noted that due to their small load and size, common small unmanned aerial vehicles cannot carry conventional survey cameras. Currently, medium - sized CCDs are often selected as the photosensitive sensor units, which have the characteristics of small volume, light weight, and relatively low price, and their spatial resolution can also meet the requirements of photography. However, due to the existence of distortion in the non - survey camera lens, the measurement results cannot meet the accuracy requirements. In order to reduce the errors brought by the non - survey camera, it is necessary to correct the distortion of the images obtained by the unmanned aerial vehicle.

[0066] In a possible implementation manner, the calculation formula for correcting the distortion error of the oblique image data is as follows:

[0067] Δx=(x - x0)(k1r 2 +k2r 2 )+P1[r 2 +2(x - x0) 2 +

[0068] P2(x - x0)(y - y0)+α(x - x0)+β(y - y0)

[0069] Δy=(y - y0)(k1r 2 +k2r 2 )+P2[r 2 +2(y - y0) 2 +2P1(x - x0)(y - y0)

[0070]

[0071] Among them, Δx represents the offset of the image point in the x-axis direction, Δy represents the offset of the image point in the y-axis direction, x0 represents the abscissa of the principal image point, y0 represents the ordinate of the principal image point, k1 and k2 represent the radial distortion coefficients, P1 and P2 represent the decentering distortion coefficients, r represents the radial distance from the image point to the principal image point, x represents the abscissa of the image point in the pixel coordinate system, y represents the ordinate of the image point in the pixel coordinate system, α represents the CCD non-square ratio coefficient, and β represents the CCD non-orthogonality distortion coefficient.

[0072] In summary, by comprehensively and meticulously correcting the errors in the oblique image data, the systematic errors and random errors in the UAV image acquisition process can be effectively reduced, thereby significantly improving the quality and accuracy of the image data and laying a solid foundation for subsequent high-precision 3D modeling and terrain analysis.

[0073] S3: Based on the error-corrected oblique image data, conduct real-scene modeling to obtain a 3D mesh model and a point cloud data file.

[0074] In a possible implementation manner, S3 specifically includes:

[0075] S301: Import the error-corrected oblique image data into the Context Capture software. After setting the parameters, submit the aerial triangulation and perform the first aerial triangulation calculation to generate a preliminary calculation result, where the preliminary calculation result includes multiple modeling images.

[0076] Among them, Context Capture is a high-precision 3D modeling software developed by Bentley Systems, designed specifically for generating high-resolution 3D models from oblique photography, point cloud, and laser scanning data. Through advanced image processing and calculation technologies, it can quickly convert photos and point cloud data into realistic 3D models and is widely used in fields such as surveying and mapping, architecture, engineering, infrastructure management, and urban planning.

[0077] Among them, aerial triangulation calculation is a core step in photogrammetry and remote sensing technologies, used to reconstruct 3D spatial information from 2D images. By calculating the geometric relationships between images and the positions of corresponding points, aerial triangulation calculation can accurately determine the exterior orientation elements of each image and integrate them into a unified spatial framework, laying a foundation for 3D modeling and geodata processing.

[0078] S302: Eliminate the invalid modeling images in the preliminary calculation result and retain the valid modeling images.

[0079] In the present invention, the operation of eliminating invalid images after preliminary calculation and retaining valid images can avoid the influence of low-quality data on the model and improve the overall quality of the modeling images.

[0080] S303: Based on the valid modeling images, import the image control points into the software for point piercing operations, and submit the second bundle adjustment calculation to obtain an optimized spatial framework.

[0081] In the present invention, after importing the image control points into the software and performing point piercing operations, the spatial framework is further optimized through the second bundle adjustment calculation, significantly improving the consistency and accuracy of the 3D model in geometric constraints.

[0082] S304: Set the modeling range for the optimized spatial framework, select the 3D mesh as the generation target, set OSGB as the export format, and specify the correct coordinate points to obtain the 3D mesh model.

[0083] S305: Select the 3D point cloud as the generation target, set LAS as the export format, and select the matching projection information to obtain the point cloud data file.

[0084] Specifically, import the image data for the first bundle adjustment calculation, check the integrity of the image data, set the corresponding parameters, click to submit the aerial triangulation, and wait for the calculation result. Delete the 8 images that cannot be used for reconstruction in the first bundle adjustment calculation, import the image control points to start point piercing to improve the calculation accuracy, and click new reconstruction after point piercing to perform the second bundle adjustment calculation. Set an appropriate modeling range for the spatial framework obtained from the second bundle adjustment, submit the project for production, and during the production configuration parameter process, select the 3D mesh as the production purpose, select the OSGB format, select the corresponding coordinate system, and click output.

[0085] Context Capture constructs the point cloud. The first two steps are the same as those of real scene modeling. Load the oblique photography photo data in the ContextCapture software, first perform the bundle adjustment calculation, submit the project for production, and during the production configuration parameter process, select the 3D point cloud as the production purpose, select the LAS format, and select the correct projection information for the spatial reference system, click output, and finally obtain the LAS format file, which is a common file format for 3D point cloud data exchange.

[0086] In summary, through the corrected high-quality data, multiple bundle adjustment calculations, effective image screening, and multi-format output, the accuracy, reliability, and practicality of the 3D model have been comprehensively improved, ensuring accurate modeling in complex terrain environments and providing strong technical support for engineering design, terrain analysis, and visualization display.

[0087] S4: Generate a digital terrain model based on the point cloud data file.

[0088] Among them, the Digital Terrain Model (DTM) is a model that represents the topographic features of the Earth's surface in digital form, usually generated by digitizing topographic elevation data. The DTM is mainly used to describe the height changes of the exposed terrain on the Earth's surface, removing non-topographic features such as buildings and vegetation, and providing pure topographic basic information.

[0089] In a possible implementation manner, S4 specifically includes:

[0090] S401: Import the point cloud data file into the Point Cloud Master software, extract the ground points from the point cloud data in the point cloud data file, and obtain the ground point elevation information.

[0091] Among them, Point Cloud Master is a professional point cloud data processing software designed for efficiently processing, analyzing, and visualizing three-dimensional point cloud data. The software provides rich tools to support users in extracting, editing, modeling, and analyzing point cloud data, and is widely used in fields such as building surveying, terrain modeling, three-dimensional real scene modeling, and engineering monitoring.

[0092] Among them, the ground point elevation information is the point elevation data that describes the exposed terrain on the Earth's surface, usually represented in the form of three-dimensional coordinates, including the horizontal positions (X, Y) and elevation values (Z) of each ground point. These information are the basic data for constructing the Digital Terrain Model (DTM), conducting terrain analysis, and carrying out engineering surveys.

[0093] S402: Generate a digital terrain model based on the ground point elevation information.

[0094] Specifically, import the point cloud format data constructed by Context Capture using the Point Cloud Master module of EarthScene. Different points may fall on the surfaces of different objects. Extract the points that fall on the ground, filter out the points that do not fall on the ground, and distinguish the two with different colors, and then the true height of the ground can be obtained. And the points of a certain classification can be displayed or hidden separately. After the ground points of the point cloud data are extracted, accurate ground point elevation information can be obtained, and a Digital Elevation Model (DEM) can be generated through these elevation values.

[0095] In the present invention, by accurately extracting the ground points in the point cloud data, the generated digital terrain model can truly reflect the height changes of the exposed terrain on the Earth's surface, avoiding the interference of non-topographic features such as buildings and vegetation, thereby providing high-precision topographic basic data. At the same time, in complex terrain environments such as mine slopes and mountains, the DTM generated based on the ground point elevation information can accurately represent the terrain undulations and landform features, providing more intuitive reference data for engineering planning and geological monitoring.

[0096] S5: Extract the contour lines of the digital terrain model and export the contour line file.

[0097] Among them, contour lines are common graphic elements on topographic maps, used to represent the elevation changes of the Earth's surface. It is a curve connecting all points with the same elevation. Through a series of contour lines, the undulation and characteristics of the terrain can be intuitively reflected.

[0098] In the present invention, by connecting points with the same elevation, contour lines can clearly and intuitively reflect the undulation of the terrain, including features such as slopes, valleys, and ridges, providing an intuitive basis for terrain analysis.

[0099] S6: According to the contour line file, use a terrain data generator to generate a three-dimensional terrain surface.

[0100] Among them, the terrain data generator is a software or tool dedicated to generating, processing, and analyzing terrain data. It can generate various forms of terrain expressions, such as three-dimensional terrain surfaces, topographic maps, and slope maps, through input elevation data (such as digital terrain models, point cloud data, contour lines, etc.).

[0101] In the present invention, the terrain data generator converts the contour line file into a three-dimensional surface through an efficient algorithm, saving modeling time and ensuring the accuracy of the generated terrain model.

[0102] In a possible implementation manner, after S6, it further includes:

[0103] Export the unit node information and node coordinate information of the three-dimensional terrain surface, and save them as TMS format files respectively.

[0104] S7: Extend the three-dimensional terrain surface downward by a preset depth to generate a three-dimensional solid slope model.

[0105] Optionally, the preset depth is 30m.

[0106] Specifically, import the TMS file format into the obtained slope surface and perform appropriate trimming. Trim 3m in the negative y-axis direction at the trailing edge, 1m in the positive y-axis direction at the leading edge, 3m in the negative x-axis direction at the right edge, and 3m in the x-axis direction at the left edge. After completion, obtain the corresponding surface; extend the surface 500m in the negative Z-axis direction to obtain a preliminary solid model. Since the solid model is symmetric about the Z-axis, that is, the lower surface of the model is a surface, the solid model needs to be cut. Considering the efficiency of subsequent mesh generation and calculation, on the premise of ensuring that it does not affect the stability analysis of the model, determine that the height from the lowest point of the model slope (610 platform) to the bottom surface of the model is 30m to obtain the corresponding solid slope model.

[0107] S8: Set the physical parameters of the slope rock and soil, and assign the Mohr-Coulomb strength criterion to the 3D solid slope model to simulate the shear failure characteristics of the rock and soil.

[0108] Among them, the Mohr-Coulomb constitutive model is a commonly used mechanical model in geotechnical engineering and geomechanics, which is used to describe the shear failure behavior of rock and soil materials under stress. This model combines the Mohr circle theory with the Coulomb shear failure criterion, and simply and effectively simulates the strength characteristics of rock and soil materials under stress state, and is an important tool in geomechanics analysis and engineering design.

[0109] It should be noted that the selection of the rock mass constitutive is an important link in numerical analysis. Different constitutives are applicable to the stress-strain relationships of different rock and soil materials. Adopting an appropriate constitutive for the research object can better carry out numerical simulation work and make the simulation data more accurate. Among the constitutives provided by Midas / GTS NX, the Mohr-Coulomb model is widely used in the shear failure of rocks and soils. Combining with the engineering geological characteristics, the Mohr-Coulomb constitutive model is selected for the slope stability analysis of each layer of soil in the slope.

[0110] In a possible implementation manner, S8 specifically includes:

[0111] S801: Set the physical parameters of the rock and soil material.

[0112] Optionally, the physical parameters include elastic modulus, Poisson's ratio, cohesion, internal friction angle, and dilation angle.

[0113] In the present invention, by defining the physical parameters of the rock and soil material (such as elastic modulus, Poisson's ratio, cohesion, internal friction angle, and dilation angle), the stress-strain relationship of the rock and soil material under stress can be completely described, providing reliable input data for accurately simulating the stability of the slope.

[0114] S802: Assign the Mohr-Coulomb strength criterion to the 3D solid slope model:

[0115]

[0116] Among them, τ represents the shear strength, c represents the cohesion, σ represents the normal stress, represents the internal friction angle.

[0117] It should be noted that under self-weight or external force, shear stress will be generated inside the rock and soil. As the stress increases, the strain will also increase. If it continues to develop, it will fail along a certain surface, and this kind of failure is called shear failure. Shear stress causes shear resistance behavior and shear resistance limit, that is, shear strength. The shear strength indexes of soil include cohesion and internal friction angle, which are often used in the analysis of stability problems such as dams and slopes.

[0118] In the present invention, endowing the model with the Mohr-Coulomb strength criterion for three-dimensional solid slopes can effectively simulate the shear behavior of geotechnical materials under self-weight or external forces, predict the critical conditions for shear failure of slopes, and ensure the scientific nature of stability analysis.

[0119] S803: Simulate the shear failure characteristics of geotechnical materials based on the Mohr-Coulomb strength criterion.

[0120] In the present invention, by simulating the shear failure characteristics of geotechnical materials, the possible failure modes and the positions of slip surfaces of slopes can be predicted, providing a reference for formulating reinforcement measures or optimizing engineering design schemes.

[0121] S9: Perform mesh division on the three-dimensional solid slope model based on the shear failure characteristics of geotechnical materials.

[0122] In a possible implementation manner, S9 specifically includes:

[0123] S901: Based on the shear failure characteristics of geotechnical materials, determine the part above the ground surface of the three-dimensional solid slope model as the overlying rock layer, and the part below the ground surface as the underlying rock layer.

[0124] In the present invention, performing hierarchical processing on the model based on the shear failure characteristics of geotechnical materials makes the mesh division more conform to the actual geotechnical physical behavior, enhancing the physical authenticity of the model and the scientific nature of stability prediction.

[0125] S902: Divide the overlying rock layer using a mesh with a size of 4 unit lengths to determine the division result of the overlying rock layer.

[0126] In the present invention, using a finer mesh division for the overlying rock layer can more accurately describe the complex terrain and stress distribution characteristics on the ground surface, contributing to a more accurate analysis of the stability of slopes near the ground surface.

[0127] S903: Divide the underlying rock layer using a mesh with a size of 20 unit lengths to determine the division result of the underlying rock layer.

[0128] In the present invention, using a sparser mesh division for the underlying rock layer reduces the computational burden and improves the overall simulation efficiency.

[0129] S904: Integrate the division result of the overlying rock layer and the division result of the underlying rock layer to obtain the mesh division result of the three-dimensional solid slope model.

[0130] S905: Export the mesh division result as a GTSNX neutral file.

[0131] Among them, the GTSNX neutral file is a data exchange format specifically used for the geotechnical engineering numerical analysis software Midas GTS NX. It is used to transfer information such as models, meshes, and material properties between different systems to ensure data compatibility and consistency.

[0132] Specifically, during mesh generation, the upper and lower rock layers are divided into two different-sized unit meshes according to different rock formations. The mesh size of the upper rock layer is 4 unit lengths, generating 57,762 nodes and 77,382 elements; the size of the lower rock layer is 20 unit lengths, generating 3,643 nodes and 12,203 elements. Finally, a total of 89,585 elements are divided in the three-dimensional model, determining the mesh generation result of the three-dimensional solid slope model.

[0133] In the present invention, the rock layers above the ground surface and those below the ground surface are divided using different mesh sizes respectively, which can effectively optimize computing resources. A finer mesh is used for the upper rock layer to ensure capturing surface details. At the same time, through a reasonable mesh generation strategy, numerical errors that may be caused by overly dense or sparse meshes are avoided, thereby improving the accuracy and stability of the simulation results.

[0134] S10: Generate a three-dimensional visualization model of the mine slope according to the mesh generation result.

[0135] In a possible implementation manner, S10 is specifically:

[0136] Convert the GTSNX neutral file of the mesh generation result into an f3prj format file, open the f3prj format file using FLAC3D software, and generate a three-dimensional visualization model of the mine slope.

[0137] Among them, the f3prj format file is a project file format specifically used for FLAC3D (Fast Lagrangian Analysis of Continuain 3Dimensions) software, which is used to store relevant information for three-dimensional numerical simulations.

[0138] Among them, FLAC3D (Fast Lagrangian Analysis of Continua in 3Dimensions) is a professional numerical simulation software developed by Itasca Company. Based on the finite difference method (FDM), it focuses on the analysis of three-dimensional problems in geotechnical engineering and geomechanics. FLAC3D is widely used in civil engineering, mining engineering, geological hazard assessment, tunneling and underground engineering, etc. due to its powerful modeling capabilities and flexibility.

[0139] In the present invention, by loading grid and attribute data through FLAC3D, a refined three-dimensional model can be generated in a complex mine slope environment, accurately reflecting the surface and underground structural features.

[0140] The beneficial effects brought by the technical solution provided by the embodiments of the present invention at least include:

[0141] (1) In the present invention, by performing error correction on the oblique image data and, on the basis of the error correction, performing real-scene modeling to generate a high-precision three-dimensional grid model and a point cloud data file, the problem of model distortion caused by data deviation is effectively avoided. Further, a digital terrain model is generated using the point cloud data to ensure that the basic terrain data of the three-dimensional model is more accurate, thereby improving the accuracy and reliability of the overall model.

[0142] (2) In the present invention, by setting the physical parameters of the slope rock and soil and assigning the Mohr-Coulomb strength criterion to the three-dimensional solid slope model to simulate the shear failure characteristics of the rock and soil, the three-dimensional solid slope model is meshed according to the rock and soil characteristics, realizing dynamic optimized meshing of different rock layers, improving the accuracy of meshing, and further improving the accuracy and reliability of the three-dimensional visualization model of the mine slope.

[0143] Refer to the attached Figure 2 description, which shows the structural schematic diagram of a three-dimensional visualization model construction system for a mine slope provided by the present invention.

[0144] The present invention also provides a three-dimensional visualization model construction system 20 for a mine slope, which is applied to the above-mentioned three-dimensional visualization model construction method for a mine slope and includes:

[0145] A processor 201.

[0146] A memory 202, on which computer-readable instructions are stored. When the computer-readable instructions are executed by the processor 201, the three-dimensional visualization model construction method for a mine slope as in the method embodiment is implemented.

[0147] The three-dimensional visualization model construction system 20 for a mine slope provided by the present invention can execute the above-mentioned three-dimensional visualization model construction method for a mine slope and achieve the same or similar technical effects. To avoid repetition, the present invention will not elaborate further.

[0148] The beneficial effects brought by the technical solution provided by the embodiments of the present invention at least include:

[0149] (1) In the present invention, by performing error correction on the inclined image data and, on the basis of the error correction, carrying out real-scene modeling to generate a high-precision three-dimensional mesh model and a point cloud data file, the problem of model distortion caused by data deviation is effectively avoided. Further, a digital terrain model is generated using the point cloud data to ensure that the basic terrain data of the three-dimensional model is more accurate, thereby improving the accuracy and reliability of the overall model.

[0150] (2) In the present invention, by setting the physical parameters of the slope rock and soil and endowing the three-dimensional solid slope model with the Mohr-Coulomb strength criterion to simulate the shear failure characteristics of the rock and soil, the three-dimensional solid slope model is meshed according to the rock and soil characteristics, realizing dynamic optimization meshing of different rock layers, improving the accuracy of meshing, and further improving the accuracy and reliability of the three-dimensional visualization model of the mine slope.

[0151] It should be understood that the processor in the embodiments of the present invention may be a central processing unit (CPU), and the processor may also be other general-purpose processors, digital signal processors (DSPs), application specific integrated circuits (ASICs), field programmable gate arrays (FPGAs) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor may be a microprocessor or the processor may also be any conventional processor, etc.

[0152] It should also be understood that the memory in the embodiments of the present invention may be a volatile memory or a non-volatile memory, or may include both volatile and non-volatile memories. Among them, the non-volatile memory may be a read-only memory (ROM), a programmable ROM (PROM), an erasable PROM (EPROM), an electrically erasable PROM (EEPROM), or a flash memory. The volatile memory may be a random access memory (RAM), which is used as an external cache. By way of example but not limitation, many forms of random access memory (RAM) are available, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDR SDRAM), enhanced SDRAM (ESDRAM), synchlink DRAM (SLDRAM), and direct rambus RAM (DR RAM).

[0153] The above embodiments can be implemented in whole or in part by software, hardware (such as circuits), firmware, or any combination thereof. When implemented using software, the above embodiments can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions or computer programs. When the computer instructions or computer programs are loaded or executed on a computer, the processes or functions described in the embodiments of the present invention are generated in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable devices. The computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, the computer instructions can be transmitted from one website, computer, server, or data center to another website, computer, server, or data center via wired (such as infrared, wireless, microwave, etc.) means. The computer-readable storage medium can be any available medium that can be accessed by a computer or a data storage device such as a server or a data center that contains one or more collections of available media. The available medium can be a magnetic medium (such as a floppy disk, a hard disk, a magnetic tape), an optical medium (such as a DVD), or a semiconductor medium. The semiconductor medium can be a solid-state drive.

[0154] It should be understood that the term "and / or" in this document is merely a description of the association relationship between associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. Here, A and B can be singular or plural. In addition, the character " / " in this document generally represents an "or" relationship between the associated objects before and after, but it may also represent an "and / or" relationship, which can be specifically understood with reference to the context.

[0155] In the present invention, "at least one" means one or more, and "a plurality" means two or more. "At least one of the following" or its similar expressions refer to any combination of these items, including any combination of single items or plural items. For example, at least one of a, b, or c can represent: a, b, c, a - b, a - c, b - c, or a - b - c, where a, b, and c can be single or multiple.

[0156] It should be understood that in various embodiments of the present invention, the magnitudes of the sequence numbers of the above processes do not mean the order of execution. The order of execution of each process should be determined by its function and internal logic, and should not constitute any limitation to the implementation process of the embodiments of the present invention.

[0157] Those of ordinary skill in the art can realize that the units and algorithm steps of each example described in combination with the embodiments disclosed herein can be implemented by electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are executed in a hardware or software manner depends on the specific application and design constraints of the technical solution. Skilled professionals can use different methods to implement the described functions for each specific application, but such implementation should not be considered to exceed the scope of the present invention.

[0158] Those skilled in the art can clearly understand that for the convenience and brevity of description, the specific working processes of the devices, apparatuses, and units described above can refer to the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0159] In several embodiments provided by the present invention, it should be understood that the disclosed devices, apparatuses, and methods can be implemented in other ways. For example, the device embodiments described above are merely illustrative. For example, the division of the units is only a logical function division, and there can be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another device, or some features can be ignored or not executed. Another point is that the displayed or discussed couplings or direct couplings or communication connections to each other can be through some interfaces, and the indirect couplings or communication connections of the devices or units can be in electrical, mechanical, or other forms.

[0160] The units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they can be located in one place, or distributed to multiple network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0161] In addition, the functional units in each embodiment of the present invention can be integrated in a processing unit, or each unit can exist physically alone, or two or more units can be integrated in one unit.

[0162] If the above-mentioned functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or a part of this technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in various embodiments of the present invention. The aforementioned storage medium includes: various media such as USB flash drives, mobile hard disks, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical discs that can store program codes.

[0163] An embodiment of the present invention provides a computer-readable storage medium, on which a computer program is stored. When the program is executed by a processor, it implements the method for constructing a three-dimensional visualization model of a mine slope as described in the method embodiment.

[0164] The computer-readable storage medium provided by the present invention can implement the steps and effects of the method for constructing a three-dimensional visualization model of a mine slope in the above method embodiment. To avoid repetition, the present invention will not elaborate further.

[0165] The beneficial effects brought by the technical solution provided by the embodiments of the present invention at least include:

[0166] (1) In the present invention, by performing error correction on the inclined image data and, on the basis of the error correction, performing real-scene modeling to generate a high-precision three-dimensional mesh model and a point cloud data file, the problem of model distortion caused by data deviation is effectively avoided. Further, a digital terrain model is generated using the point cloud data to ensure that the basic terrain data of the three-dimensional model is more accurate, thereby improving the accuracy and reliability of the overall model.

[0167] (2) In the present invention, by setting the physical parameters of the slope rock and soil and assigning the Mohr-Coulomb strength criterion to the three-dimensional solid slope model to simulate the shear failure characteristics of the rock and soil, the three-dimensional solid slope model is meshed according to the rock and soil characteristics, realizing dynamic optimization meshing of different rock layers, improving the accuracy of meshing, and further improving the accuracy and reliability of the three-dimensional visualization model of the mine slope.

[0168] As described above, the above are only specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention can easily think of changes or substitutions, which should all be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention should be subject to the protection scope of the claimed rights.

[0169] The following points need to be explained:

[0170] (1) The accompanying drawings of the embodiments of the present invention only relate to the structures involved in the embodiments of the present invention, and other structures can refer to the general design.

[0171] (2) For clarity, in the accompanying drawings used to describe the embodiments of the present invention, the thickness of layers or regions is enlarged or reduced, that is, these drawings are not drawn to actual scale. It can be understood that when an element such as a layer, film, region or substrate is referred to as being "on" or "under" another element, the element can be "directly" on or under the other element or there can be intervening elements.

[0172] (3) Without conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other to obtain new embodiments.

[0173] The above is only the specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. The protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. A method for constructing a three-dimensional visualization model of a mine slope, characterized in that, Including: S1: Obtain the inclined image data of the mine slope; S2: Perform error correction on the inclined image data; S3: Based on the error-corrected inclined image data, conduct real-scene modeling to obtain a three-dimensional grid model and a point cloud data file; S4: Generate a digital terrain model according to the point cloud data file; S5: Extract the contour lines of the digital terrain model and export the contour line file; S6: Generate a three-dimensional terrain surface according to the contour line file using a terrain data generator; S7: Extend the three-dimensional terrain surface downward by a preset depth to generate a three-dimensional solid slope model; S8: Set the physical parameters of the slope rock and soil, and endow the three-dimensional solid slope model with the Mohr-Coulomb strength criterion to simulate the shear failure characteristics of the rock and soil; S9: Based on the shear failure characteristics of the rock and soil, perform mesh division on the three-dimensional solid slope model; S10: Generate a three-dimensional visualization model of the mine slope according to the mesh division result.

2. The method for constructing a three-dimensional visualization model of a mine slope according to claim 1, wherein, The specific content of S2 includes: Correct the distortion error of the inclined image data; Correct the exterior orientation element error caused by the UAV flight attitude deviation in oblique photography; Correct the image displacement error through shortening the exposure time and image motion compensation technology; Correct the control point coordinate error by accurately measuring the image control points; Correct the marked position of the control points in the image and the piercing point error caused by complex terrain or blurred markings.

3. The method for constructing a three-dimensional visualization model of a mine slope according to claim 2, characterized in that The calculation formula for correcting the distortion error of the inclined image data is: Δx = (x - x0)(k1r 2 + k2r 2 ) + P1[r 2 + 2(x - x0) 2 + P2(x - x0)(y - y0)+α(x - x0)+β(y - y0) Δy = (y - y0)(k1r 2 + k2r 2 ) + P2[r 2 + 2(y - y0) 2 + 2P1(x - x0)(y - y0) Where, Δx represents the offset of the image point in the x-axis direction, Δy represents the offset of the image point in the y-axis direction, x0 represents the abscissa of the image principal point, y0 represents the ordinate of the image principal point, k1 and k2 represent the radial distortion coefficients, P1 and P2 represent the decentering distortion coefficients, r represents the radial distance from the image point to the image principal point, x represents the abscissa of the image point in the pixel coordinate system, y represents the ordinate of the image point in the pixel coordinate system, α represents the CCD non-square ratio coefficient, and β represents the CCD non-orthogonality distortion coefficient.

4. The method for constructing a three-dimensional visualization model of a mine slope according to claim 1, wherein, The specific content of S3 includes: S301: Import the error-corrected inclined image data into the Context Capture software, set the parameters and submit the aerial triangulation for the first time to perform the first air triangulation calculation to generate a preliminary calculation result, where the preliminary calculation result includes multiple modeling images; S302: Eliminate the invalid modeling images in the preliminary calculation result and retain the valid modeling images; S303: Based on the valid modeling images, import the image control points into the software for piercing operations and submit the second air triangulation calculation to obtain an optimized spatial framework; S304: Set the modeling range for the optimized spatial framework, select the three-dimensional grid as the generation target, set the OSGB as the export format, and specify the correct coordinate points to obtain the three-dimensional grid model; S305: Select the three-dimensional point cloud as the generation target, set the LAS as the export format, and select the matching projection information to obtain the point cloud data file.

5. The method for constructing a three-dimensional visualization model of a mine slope according to claim 1, characterized in that, The specific content of S4 includes: S401: Import the point cloud data file into the Point Cloud Master software, extract the ground points from the point cloud data in the point cloud data file, and obtain the ground point elevation information; S402: Generate a digital terrain model based on the ground point elevation information.

6. The method for constructing a three-dimensional visualization model of a mine slope according to claim 1, wherein After the S6, it further includes: Export the element node information and node coordinate information of the three-dimensional terrain surface, and save them as TMS format files respectively.

7. The method for constructing a three-dimensional visualization model of a mine slope according to claim 1, wherein The S8 specifically includes: S801: Set the physical parameters of the geotechnical material; S802: Assign the Mohr-Coulomb strength criterion to the three-dimensional solid slope model; Among them, τ represents the shear strength, c represents the cohesion, and σ represents the normal stress. represents the angle of internal friction; S803: Simulate the shear failure characteristics of the geotechnical material based on the Mohr-Coulomb strength criterion.

8. The method for constructing a three-dimensional visualization model of a mine slope according to claim 1, wherein, The S9 specifically includes: S901: Based on the shear failure characteristics of the geotechnical material, determine the part above the ground surface of the three-dimensional solid slope model as the overlying rock layer, and the part below the ground surface as the underlying rock layer; S902: Divide the overlying rock layer with a grid of 4 unit lengths to determine the division result of the overlying rock layer; S903: Divide the underlying rock layer with a grid of 20 unit lengths to determine the division result of the underlying rock layer; S904: Integrate the division result of the overlying rock layer and the division result of the underlying rock layer to obtain the grid division result of the three-dimensional solid slope model; S905: Export the grid division result as a GTSNX neutral file.

9. The method for constructing a three-dimensional visualization model of a mine slope according to claim 8, wherein, The S10 is specifically: Convert the GTSNX neutral file of the grid division result into an f3prj format file, open the f3prj format file using the FLAC3D software, and generate a three-dimensional visualization model of the mine slope.

10. A three-dimensional visualization model construction system for a mine slope, characterized in that, It includes: A processor; A memory, on which computer-readable instructions are stored. When the computer-readable instructions are executed by the processor, the method for constructing a three-dimensional visualization model of a mine slope as described in any one of claims 1 to 9 is implemented.

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