Method for estimating landslide volume and constructing landslide calculation model

Abstract

The invention relates to a method for estimating the volume of a landslide mass and constructing a landslide calculation model, and the method comprises the steps: S1, obtaining geological data, and constructing an original geological model representing the geological state before landslide; s2, acquiring landslide topographic data, and constructing a landslide geologic model representing a landslide geologic state; s3, engraving on the original geological model by applying a triangulation network engraving technology to form an engraving model with a sliding surface; s4, performing set operation on the sculpture model and the original geologic model, and extracting a difference part to form a landslide mass model; wherein through the triangulation network engraving operation in the step S3, grid nodes of a sliding surface in the geologic model formed after engraving and grid nodes at corresponding positions in the original geologic model are kept in spatial position consistency, and based on the landslide mass model formed in the step S4, the volume of the landslide mass is estimated, and a landslide calculation model is constructed. The invention aims to improve the precision of estimating the volume of the landslide mass and the reliability of a calculation model, and provides powerful support for landslide disaster prevention and control.

Description

Technical Field

[0001] The present invention relates to the technical field of highway slope engineering stability assessment, and in particular to a method for estimating the volume of a landslide body and constructing a landslide calculation model. Background Art

[0002] Landslides, a common geological hazard, pose a serious threat to human life, property, and infrastructure. Accurately estimating landslide volume and building reliable landslide models are critical for landslide risk assessment, prevention and control engineering design, and emergency response decision-making. Researchers and engineers have long been dedicated to developing effective landslide volume estimation and modeling technologies. However, existing technologies still have limitations in terms of accuracy, efficiency, and model reliability.

[0003] Traditional methods for estimating landslide volume rely primarily on manual on-site surveys and traditional topographic surveying techniques. For example, by surveying the landslide's boundaries on the ground and using tools such as tape measures and compasses to obtain geometric information about the landslide's dimensions, geometric volume calculation methods (such as the average cross-section method and grid method) are then used in conjunction with topographic maps or contour maps to estimate the landslide's volume. These traditional methods played an important role in early landslide research and engineering practice. However, with the increasing demand for more sophisticated and dynamic landslide disaster prevention and control, the limitations of these traditional methods have become increasingly apparent. First, manual on-site surveys and measurements are labor-intensive and inefficient, especially in areas with complex terrain, dense vegetation, or inaccessible transportation. Measurements are more difficult and time-consuming, making them difficult to meet the requirements of rapid response and emergency response. Second, traditional surveying methods have limited accuracy. Due to factors such as measuring tool accuracy, human error, and topographic conditions, it is difficult to obtain high-precision landslide geometry information, resulting in inaccurate volume estimates. In addition, traditional methods make it difficult to dynamically monitor changes in landslide bodies and cannot promptly reflect the deformation and development trends of landslide bodies, which is not conducive to dynamic early warning and prevention of landslide disasters.

[0004] In the early days of landslide computational modeling, simplified models and empirical formulas were primarily used for landslide stability analysis and prediction. With the advancement of computer technology and numerical computational methods, landslide computational models based on numerical methods such as the finite element method, finite difference method, and discrete element method have become widely used. Traditional landslide computational modeling methods typically model the landslide body (slip body) and the landslide bed (base) separately. For example, a three-dimensional geometric model of the landslide body is first constructed based on geological exploration data and topographic data, followed by a separate model of the landslide bed. The slip body model and the base model are then assembled to form a complete landslide computational model. However, this separate modeling and assembly approach has a significant technical drawback: the mesh nodes of the slip body model and the base model are often not precisely aligned on the sliding surface (slip surface) between the landslide body and the landslide bed. This inconsistency in mesh nodes leads to poor stress transfer and deformation coordination at the sliding surface, affecting the accuracy of the stress and strain distributions in the numerical simulation, and thus reducing the predictive performance of the overall computational model. Especially when performing refined numerical simulations, the discontinuity of the sliding surface mesh nodes will introduce large numerical errors, seriously affecting the reliability of the calculation results.

[0005] In addition, traditional landslide calculation models based on digital elevation maps (DEMs) have a contradiction between model accuracy and computational efficiency. In order to improve model accuracy, high-resolution DEM data is required and fine finite element or finite difference grids are constructed. However, high-resolution DEM data often leads to a huge number of model grids. Especially in three-dimensional modeling, the number of model grids can reach millions or even tens of millions. The huge number of grids significantly increases the complexity of the calculation model, resulting in excessive calculation time, excessive consumption of computing resources, and low computational efficiency, making it difficult to meet the needs of fast calculation and real-time analysis in engineering practice. Especially in the scenarios of emergency response and rapid assessment of landslide disasters, the bottleneck problem of computational efficiency is particularly prominent.

[0006] Therefore, in response to the above-mentioned problems existing in the existing technology, it is urgent to develop a high-precision and high-efficiency landslide volume estimation method and landslide calculation model construction technology to improve the scientific and technological level and engineering application capabilities of landslide disaster prevention and control. Summary of the Invention

[0007] In order to solve the problems existing in the prior art to a certain extent as much as possible, the present invention discloses a method for estimating the volume of landslide volume and constructing a landslide calculation model, aiming to improve the accuracy of landslide volume estimation and the reliability of the calculation model, and provide strong support for landslide disaster prevention and control.

[0008] The present invention provides a method for estimating the volume of a landslide and constructing a landslide calculation model, comprising the following steps:

[0009] First, step S1 is performed, which involves acquiring geological data and constructing an original geological model representing the geological state before the landslide. This step aims to establish a three-dimensional digital model of the initial topography and geological structure before the landslide occurred. Specifically, a variety of geological data sources, such as existing contour data, historical elevation data, geological exploration reports, and borehole data, can be utilized. Using professional terrain modeling software and geological modeling techniques, a digital model can be constructed that accurately reflects the surface morphology and potential geological structural characteristics of the study area before the landslide occurred. This original geological model serves as a baseline model for subsequent steps, providing an initial reference for the identification and calculation of landslide bodies.

[0010] Then, step S2 is performed to obtain post-landslide topographic data and construct a post-landslide geological model that characterizes the geological state after the landslide. This step aims to obtain surface morphological data after the landslide actually occurs and construct a corresponding digital model. To further improve modeling accuracy, an unmanned aerial vehicle (UAV) equipped with an RTK (Real-time Kinematic) high-precision positioning system can be used for rapid and efficient terrain data acquisition. The photogrammetry equipment onboard the UAV can obtain high-resolution image data. Through subsequent image processing and three-dimensional reconstruction technology, a detailed post-landslide geological model can be constructed. This model accurately records the changes in surface morphology after the landslide occurs, providing a direct data basis for the subsequent identification and measurement of the landslide body.

[0011] After obtaining the original geological model and the post-landslide geological model, step S3 is entered, in which triangulated mesh carving technology is applied to the original geological model to carve a sculptured model with a sliding surface. This step is one of the core technical features of the present invention. Triangulated mesh carving technology is a digital terrain analysis method whose core concept is to perform operations similar to manual carving on a digital model. In the present invention, the post-landslide geological model is used as a reference for carving, and "carving" is performed on the original geological model along the area where the landslide occurred. That is, the triangulated mesh of the original geological model is locally adjusted and deformed so that its surface morphology gradually approaches the surface morphology of the post-landslide geological model. The key to the carving process is to precisely control the depth and range of the carving until the sliding surface of the landslide is clearly presented on the original geological model. It is particularly emphasized that through the precise triangulated mesh carving operation, it can be ensured that the grid nodes of the sliding surface in the geological model formed after carving maintain a high degree of spatial consistency with the grid nodes at the corresponding positions in the original geological model. This consistency of grid nodes provides an important geometric foundation for subsequent set operations and numerical simulation analysis.

[0012] Finally, step S4 is performed, i.e., performing a set operation on the engraved model and the original geological model to extract the differences and form a landslide model. This step utilizes set operation methods in computer graphics, such as the difference operation in Boolean operations, to spatially superimpose and compare the engraved model with the original geological model. Since the engraved model is formed by "engraving" the landslide area based on the original geological model, the difference between the two is the spatial range occupied by the landslide body. Through set operations, this difference can be accurately extracted, thereby forming an independent landslide model. This landslide model not only contains the three-dimensional geometric morphological information of the landslide body, but also, because its construction process is closely linked to the original geological model and the post-landslide geological model, it can accurately reflect the position and morphological characteristics of the landslide body in the original terrain. Based on this landslide model, it is possible to further accurately estimate the volume of the landslide body and construct numerical calculation models for landslide stability analysis, dynamic simulation, etc.

[0013] According to the method for estimating the volume of a landslide and constructing a landslide calculation model of the present invention, in step S1, the method further includes:

[0014] Step 1.1, collecting at least one of contour data, historical elevation data, and drilling data, or a combination thereof as the geological data;

[0015] Step 1.2: Based on the collected geological data, an initial triangulated network model is generated using a triangulation algorithm;

[0016] Step 1.3: Edit and modify the initial triangulated network model to obtain the original geological model.

[0017] As you can understand, step 1.1 specifies the data sources used to construct the original geological model. Contour data, historical elevation data, and borehole data can be used individually or in combination. Contour data provides a macroscopic representation of the surface undulations, historical elevation data provides information on surface changes over time, and borehole data reveals the structure of the subsurface rock and soil layers. The integration of multiple data sources allows for the acquisition of geological information from different dimensions and levels of accuracy, providing a data foundation for the subsequent construction of a highly accurate and reliable original geological model. Since step 1.1 allows for the use of multiple geological data sources, it fully utilizes existing geological information, improving the comprehensiveness and accuracy of data input, and thereby enhancing the accuracy and reliability of the original geological model, enabling it to more realistically reflect the geological conditions prior to the landslide. Step 1.2, on the other hand, utilizes a triangulation algorithm to convert discrete geological data (such as contour points and elevation points) into a continuous triangular mesh model. Triangulated mesh models effectively approximate complex terrain surfaces and are widely used in geographic information systems and engineering modeling. The use of a triangulation algorithm enables automated and rapid generation of an initial terrain surface model from geological data, providing a foundational framework for subsequent model editing and optimization. Step 1.2 utilizes a triangulation algorithm to automatically convert discrete data into a continuous model. Compared to traditional manual modeling methods, this significantly improves modeling efficiency and shortens the modeling cycle. Finally, Step 1.3 emphasizes the importance of manual or semi-automatic editing and correction of the initial triangulated mesh model. Because raw geological data may contain errors, noise, or missing data, the initial triangulated mesh model generated directly from the raw data may contain defects such as topological errors and rough surfaces. Manual editing and correction can effectively eliminate or mitigate these defects, such as smoothing the model surface, correcting topological errors, and filling in missing data areas, resulting in a more accurate and reliable original geological model. Step 1.3 effectively eliminates potential defects in the initial model through model editing and correction, ensuring its quality and enhancing its reliability. This provides a high-quality foundation for subsequent landslide volume estimation and computational model construction.

[0018] According to the method for estimating the volume of a landslide and constructing a landslide calculation model of the present invention, in step 1.3, the method further includes:

[0019] Manually correct the erroneous triangles in the initial triangulated network model caused by data defects. It can be understood that data defects, such as data point errors, missing data points, etc., may cause the triangulation algorithm to generate erroneous triangles, such as self-intersecting triangles, narrow triangles, etc. These erroneous triangles will seriously affect the quality of the model and the accuracy of subsequent calculations. Manually correcting erroneous triangles, such as adjusting node positions, re-dividing triangles, etc., can effectively eliminate topological errors and geometric errors in the model, and ensure the correctness and reliability of the model. Correcting erroneous triangles eliminates the geometric and topological errors in the model caused by data defects, improves the geometric accuracy and topological correctness of the model, enables the model to more accurately express the original geological state, and provides a more reliable basis for subsequent landslide volume estimation and calculation model construction, and ultimately improves the reliability of landslide analysis results.

[0020] According to the method for estimating the volume of a landslide and constructing a landslide calculation model of the present invention, in step S2, the method further includes:

[0021] Step 2.1: Use a drone equipped with an RTK high-precision positioning system to collect image data of the landslide area according to a preset route to obtain post-landslide terrain data;

[0022] Step 2.2: Process the post-landslide terrain data using photogrammetry technology to generate the post-landslide geological model, wherein the post-landslide geological model is a triangulated network model with a model accuracy of centimeter level.

[0023] As you can understand, step 2.1 utilizes a drone equipped with a high-precision RTK (Real-Time Kinematic) positioning system to collect post-landslide terrain data. RTK technology provides centimeter-level positioning accuracy, giving the drone-collected terrain data extremely high spatial precision. Drones are flexible and efficient, enabling rapid and safe acquisition of high-resolution imagery of the landslide area, overcoming the difficulties and risks associated with traditional ground-based surveying methods in landslide areas. The pre-set flight path ensures image data coverage and overlap, ensuring high-quality data for subsequent photogrammetric processing. Step 2.2 utilizes photogrammetry to convert the drone-collected image data into a three-dimensional terrain model. Photogrammetry is a mature, high-precision 3D reconstruction technology capable of extracting 3D information from multiple images, generating high-precision point cloud data and triangulated mesh models. The resulting post-landslide geological model is a triangulated mesh model, maintaining the same data structure as the original geological model, facilitating subsequent model overlay and computation. The centimeter-level model accuracy ensures that the post-landslide geological model can accurately reflect the topographic and geomorphological characteristics after the landslide occurs, providing a high-precision data foundation for subsequent landslide body identification and volume estimation. In summary, the use of drones for data collection has greatly improved data collection efficiency and shortened data acquisition time. Especially in dangerous areas such as landslides, drone operations can effectively avoid personnel safety risks. In addition, the combined application of RTK technology and photogrammetry technology ensures the centimeter-level accuracy of the post-landslide geological model, which can accurately capture the detailed information of the topography and geomorphology after the landslide occurs, providing high-resolution data support for subsequent landslide body identification and analysis. Furthermore, the generated post-landslide geological model is a triangulated network model, which is consistent with the data structure of the original geological model, reducing the complexity of data format conversion and facilitating subsequent model superposition, calculation and analysis.

[0024] According to the method for estimating the volume of a landslide and constructing a landslide calculation model of the present invention, in step 2.2, the method further includes:

[0025] The post-landslide terrain data is subjected to image stitching, geometric correction and three-dimensional reconstruction processing to generate the post-landslide geological model.

[0026] As you can understand, step 2.2 defines the key steps in photogrammetry processing, including image stitching, geometric correction, and 3D reconstruction. Image stitching combines multiple drone-collected images into a single, complete image, providing the basic image data for subsequent geometric correction and 3D reconstruction. Geometric correction eliminates image distortion and errors, converts the image data to a unified geographic coordinate system, and ensures the geometric accuracy of the image data. 3D reconstruction utilizes the overlapping areas of multi-view images and, through algorithms such as stereo matching, extracts 3D information from the images, generates point cloud data, and ultimately constructs a triangulated network model. These interlinked processing steps ensure the accuracy and reliability of the post-landslide geological model. In summary, image stitching ensures complete coverage of image data in the landslide area, avoids data loss, and provides a complete data basis for subsequent three-dimensional reconstruction. Geometric correction eliminates geometric distortion and errors in the image, improves the geometric accuracy of the image data, and thus improves the geometric accuracy of the post-landslide geological model reconstructed based on the image data, ensuring the spatial position accuracy of the model. The three-dimensional reconstruction process extracts three-dimensional information from multi-view images, truly restoring the three-dimensional morphology of the terrain after the landslide occurs, so that the post-landslide geological model can accurately express the spatial distribution characteristics of the landslide body.

[0027] According to the method for estimating the volume of a landslide and constructing a landslide calculation model of the present invention, step S3 further includes:

[0028] Step 3.1, superimposing the post-landslide geological model on the original geological model;

[0029] Step 3.2, performing a triangulation operation on the original geological model with the landslide range indicated by the post-landslide geological model as the boundary;

[0030] Step 3.3: Continue the engraving operation until a sliding surface is revealed in the engraving area, then stop engraving to obtain the engraving model.

[0031] As can be understood, step 3.1 superimposes the post-landslide geological model on the original geological model. The purpose is to use the post-landslide geological model to indicate the area and scope of the landslide, providing a spatial reference for subsequent triangulation operations. This model overlay allows spatial alignment of post-landslide geomorphological changes with the original geomorphological information, providing a positioning basis for accurately carving the landslide body. Step 3.2 defines the scope of the triangulation operation, using the landslide scope indicated by the post-landslide geological model as the boundary. This means that the carving operation will be performed on the original geological model along the area where the landslide occurred, with the carving boundary determined by the post-landslide geological model, ensuring the accuracy and specificity of the carving area. Triangulation carving technology can locally modify and deform the triangulation model, simulating the removal of surface soil, thereby revealing the sliding surface of the landslide body. Step 3.3 defines the termination condition for the triangulation operation: carving stops when the sliding surface is revealed in the carved area. The exposure of the sliding surface indicates that the boundary and morphology of the landslide body have been essentially determined. Through manual observation or algorithm recognition, when the terrain characteristics of the engraving area meet the characteristics of the sliding surface, the engraving can be stopped and the final engraving model can be obtained. The engraving model retains the overall shape of the original geological model, and the landslide body and sliding surface are engraved in the landslide area, providing a basis for the subsequent landslide body model extraction and sliding surface analysis. In summary, this embodiment indicates the landslide range through the post-landslide geological model, ensures the regional accuracy of the triangulation engraving operation, avoids invalid engraving and erroneous engraving, and improves the engraving efficiency and accuracy. The triangulation engraving technology can simulate the soil removal process, gradually revealing the sliding surface hidden under the original surface, so that the spatial shape of the sliding surface can be clearly presented, providing an intuitive terrain basis for the subsequent sliding surface modeling and landslide analysis. In addition, the engraving model not only retains the overall geomorphological information of the original geological model, but also finely depicts the landslide body and sliding surface in the landslide area, providing a rich information basis for the subsequent landslide body model extraction and sliding surface analysis.

[0032] According to a method for estimating landslide volume and constructing a landslide calculation model of the present invention, step S3 further includes:

[0033] When performing triangulated mesh carving operations, the carving depth and carving direction are controlled so that the mesh nodes of the sliding surface in the carving model and the mesh nodes of the original geological model at positions corresponding to the sliding surface are spatially overlapped.

[0034] As you can understand, the triangulated mesh carving process requires precise control of the carving depth and direction. The goal is to spatially overlap the mesh nodes at the sliding surface in the carved model with the mesh nodes at the corresponding locations on the sliding surface in the original geological model. This node overlap ensures topological consistency between the carved model and the original geological model at the sliding surface. Topological consistency is crucial for subsequent numerical simulation analysis, as it prevents mesh breaks or misalignments at the sliding surface and ensures the accuracy and stability of the numerical simulation. In summary, this embodiment precisely controls the engraving depth and direction so that the mesh nodes of the sliding surface coincide with the corresponding nodes of the original model, thereby ensuring the topological continuity of the model at the sliding surface position, avoiding mesh gaps or overlaps, and providing a good mesh foundation for subsequent numerical simulation analysis. The topological consistency of the sliding surface avoids the numerical error caused by mesh discontinuity at the sliding surface position, improves the accuracy and reliability of the numerical simulation, and enables the simulation results to more realistically reflect physical phenomena such as stress distribution and displacement field changes during the landslide process. The engraving model with sliding surface topological consistency is more suitable for numerical simulation methods such as finite element analysis and discrete element analysis, which expands the application scope of the model and enables it to better serve application scenarios such as landslide stability analysis, risk assessment and early warning.

[0035] According to the method for estimating the volume of a landslide and constructing a landslide calculation model of the present invention, in step S4, the method further includes:

[0036] Step 4.1, performing a Boolean difference operation on the engraved model and the original geological model to obtain a difference model including the landslide body;

[0037] Step 4.2: Extract the portion that overlaps with the post-landslide geological model space from the difference model as the landslide body model.

[0038] It can be understood that step 4.1 uses a Boolean difference operation to subtract the engraving model from the original geological model to obtain the difference between the two. Since the engraving model is formed by removing part of the landslide body soil from the original geological model through the engraving operation, the result of the Boolean difference operation will mainly contain the removed soil part, that is, the landslide body. The resulting difference model will clearly show the spatial range and morphology of the landslide body. And through step 4.2, the difference model is further screened to extract the part that overlaps with the post-landslide geological model in space as the final landslide body model. The post-landslide geological model indicates the approximate spatial range of the landslide body. By performing spatial overlap analysis with the post-landslide geological model, the boundary of the landslide body can be further accurately defined, and the non-landslide body parts that may exist in the difference model, such as the small error area caused by the engraving operation, can be removed, thereby obtaining a more accurate and pure landslide body model. In summary, this embodiment can accurately extract the landslide body part from the original geological model and the carving model through Boolean difference operation and spatial overlap analysis, avoiding the error and subjectivity of manually outlining the landslide body boundary, and improving the accuracy and objectivity of the landslide body model extraction. The extracted landslide body model has a clear boundary and can accurately reflect the spatial range and morphology of the landslide body, providing an accurate geometric model for subsequent landslide body volume estimation and calculation model construction. Furthermore, through spatial overlap analysis with the post-landslide geological model, the non-landslide body part that may exist in the difference model is effectively removed, thereby improving the purity of the landslide body model, making the model more focused on the landslide body itself, and providing a more reliable model basis for subsequent landslide analysis.

[0039] According to the method for estimating the volume of a landslide and constructing a landslide calculation model of the present invention, after step S4, further comprises step S5:

[0040] Based on the landslide body model, landslide body volume calculation is performed and a landslide calculation model is constructed for subsequent landslide stability analysis, landslide risk assessment or landslide numerical simulation analysis.

[0041] This step is based on the subsequent application of the landslide body model, including landslide body volume calculation and construction of the landslide calculation model, further pointing out the application direction of the landslide calculation model, such as landslide stability analysis, landslide risk assessment and landslide numerical simulation analysis. This means that the landslide body model constructed by the present invention can not only be used for volume estimation, but also can be used as a basic model for landslide analysis and prediction, with wide application value. Its technical effect is: based on the accurate landslide body model, high-precision landslide body volume calculation can be carried out, providing accurate data support for disaster assessment, engineering quantity calculation and resource allocation, and the constructed landslide calculation model can be used for subsequent landslide stability analysis, risk assessment and numerical simulation analysis, providing a scientific decision-making basis for landslide disaster prevention and control, and the landslide body model can be applied to multiple fields such as landslide stability analysis, landslide risk assessment, landslide numerical simulation analysis, providing comprehensive technical support for landslide disaster prevention and control, with wide application prospects.

[0042] According to a method for estimating landslide volume and constructing a landslide calculation model of the present invention, the landslide numerical simulation analysis includes using finite element analysis or discrete element analysis method to simulate and analyze stress distribution, displacement field changes and potential dangerous areas during the landslide process.

[0043] As you can understand, this step lists two commonly used numerical simulation methods: finite element analysis (FEA) and discrete element analysis (DEA). The goal of these numerical simulations is to analyze the stress distribution, displacement field changes, and potential hazardous areas during a landslide. FEA and DEA are two well-established numerical simulation methods that effectively simulate the mechanical behavior of complex media. Using these two methods to numerically simulate landslide processes can provide a deep understanding of the movement mechanisms of landslides, predict their trends and extent, and provide a scientific basis for landslide disaster prevention and control. The technical benefits achieved include simulating the stress distribution and displacement field changes of landslide bodies under various conditions, providing a deeper understanding of the mechanical behavior and failure mechanisms of landslides, and providing a theoretical foundation for landslide stability analysis and the design of prevention measures. Furthermore, numerical simulations can predict the movement trends, speeds, and extents of landslides under different conditions, providing a scientific basis for landslide risk assessment and early warning. Furthermore, numerical simulation analysis can identify stress concentration areas and displacement deformation areas inside and around the landslide body, thereby accurately identifying potential dangerous areas and providing important information support for landslide disaster prevention and control and engineering safety.

[0044] The various steps of this embodiment together constitute a complete, efficient, and high-precision method system for estimating landslide volume and constructing a landslide calculation model. This method system can effectively solve the problems existing in the prior art, such as low landslide volume estimation accuracy, insufficient calculation model modeling accuracy, and high calculation complexity. It provides strong technical support for landslide disaster prevention and control, and has significant technological advancement and practical value.

[0045] The technical effects of the method for estimating landslide volume and constructing a landslide calculation model of the present invention are as follows:

[0046] 1. Improving the accuracy of landslide volume estimation: The acquisition of post-landslide terrain data using a drone equipped with a high-precision RTK positioning system in step S2 and the construction of a high-precision original geological model in step S1 provide a high-precision data foundation for subsequent landslide identification and measurement. Step S4, extracting the landslide model through precise set operations, more accurately defines the boundaries and extent of the landslide, significantly improving the accuracy of landslide volume estimation to centimeter-level accuracy. Compared to traditional methods, this significantly reduces measurement errors and improves the reliability of the estimation results.

[0047] 2. Improving the accuracy of the landslide calculation model: Step S3 utilizes triangulated mesh carving technology, with particular emphasis on maintaining spatial consistency between the sliding surface mesh nodes and the original geological model mesh nodes. This ensures precise alignment of the sliding surface mesh nodes of the landslide model and the original geological model. This consistent mesh node alignment effectively addresses the issue of precise alignment of sliding surface mesh nodes in traditional modeling methods, ensuring geometric continuity and consistency of the model. This provides a more accurate geometric model foundation for subsequent numerical simulation analysis, reduces discretization errors in numerical simulations, and improves the reliability of simulation results.

[0048] 3. Reduce computational complexity and improve computational efficiency: The method of the present invention performs carving and set operations based on a high-precision triangulated mesh model, thus avoiding the problem of an excessively large number of model meshes that may occur in traditional methods. At the same time, the triangulated mesh carving technology of step S3 can effectively and accurately "carve" the landslide body on the original geological model without the need for complex mesh reconstruction, thereby reducing the complexity of model construction. The set operation of step S4 can also efficiently extract the landslide body model. Overall, the method of the present invention effectively reduces computational complexity and improves computational efficiency while ensuring model accuracy, thereby making rapid response and real-time analysis possible.

[0049] 4. Rapid Construction and Visual Analysis of Landslide Models: The method presented here features a clear workflow and concise steps. Combining drone data acquisition with computer-automated processing technology, it enables rapid construction of landslide models. The resulting three-dimensional landslide model facilitates visualization and analysis of the landslide from various angles and scales, intuitively displaying its spatial morphology and characteristics. This improves the intuitiveness and credibility of the calculation results, providing an intuitive and effective tool for landslide disaster analysis, assessment, and prevention.

[0050] 5. Wide range of application scenarios: The landslide model constructed based on the method of the present invention can not only be used for accurate estimation of the volume of the landslide, but also serve as a basic model for landslide stability analysis, landslide risk assessment and landslide early warning system construction. It can simulate the dynamic behavior of landslides under different working conditions, evaluate the stability of landslides under the influence of factors such as rainfall, earthquakes, and human activities, and provide quantitative decision-making support for geological disaster prevention and control. It has a wide range of application scenarios and has important engineering application value and social benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0052] Figure 1 It is a schematic diagram of the original geological model constructed by the present invention;

[0053] Figure 2 It is a schematic diagram of the geological model after the landslide occurs constructed by the present invention;

[0054] Figure 3 It is a schematic diagram of carving a landslide model using triangulated mesh carving technology in the present invention;

[0055] Figure 4 This is a schematic diagram of a post-landslide geological model carved using triangulated mesh carving technology in the present invention;

[0056] Figure 5 It is a schematic diagram of a landslide model formed by performing collective calculations on the original geological model and the carved geological model in the present invention.

[0057] Reference numerals:

[0058] none. DETAILED DESCRIPTION

[0059] The following describes embodiments of the present invention in detail. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended only to explain the present invention and are not to be construed as limiting the present invention.

[0060] like Figures 1 to 5 As shown, a method for estimating the volume of a landslide and constructing a landslide calculation model in this embodiment specifically includes the following main steps and various branch steps:

[0061] Step S1: Acquire geological data and construct an original geological model representing the geological state before the landslide;

[0062] Step S1 is to construct a 3D model that can reflect the landform characteristics and geological structure before the landslide occurs, which serves as the basis for subsequent landslide body identification and calculation. In this embodiment, contour data is used as the data source for constructing the original geological model.

[0063] Step 1.1, collecting at least one of contour data, historical elevation data, and drilling data, or a combination thereof as the geological data;

[0064] In step 1.1, a highway slope area is selected as the research object. First, contour data for the area is obtained by consulting topographic map data. This contour data is stored in vector format and contains contour information describing the surface undulations. In other embodiments, historical elevation data (such as early DEM data) and borehole data (such as depth information of stratigraphic interfaces) can also be combined to more comprehensively describe the geological structure.

[0065] Step 1.2: Based on the collected geological data, an initial triangulated network model is generated using a triangulation algorithm;

[0066] In step 1.2, after obtaining the contour data, use professional terrain modeling software, such as ArcGIS, Surfer, or Geomagic Freeform, to import the contour data into the software. The software uses a triangulation algorithm, such as the Delaunay triangulation algorithm or the Voronoi triangulation algorithm, to generate an initial triangulated mesh model based on the contour data points. The triangulation algorithm can effectively convert discrete contour data into continuous triangular facets, thereby constructing a preliminary terrain surface. The generated initial triangulated mesh model consists of a series of interconnected triangular facets, and the vertices of each triangle are located on the original contour data points, thus preliminarily characterizing the terrain undulation characteristics of the study area.

[0067] Step 1.3, editing and correcting the initial triangulated network model to obtain the original geological model;

[0068] In step 1.3, the initial triangulated network model generated may have some problems caused by data quality or algorithm limitations, such as isolated triangles, erroneous patches, etc. In order to ensure the accuracy and quality of the original geological model, the initial triangulated network model needs to be manually edited and corrected.

[0069] In addition, step 1.3 may also include manually correcting erroneous triangular facets in the initial triangulated mesh model caused by data defects.

[0070] Specifically, the initial triangulated mesh model may still contain some erroneous triangles due to defects in the contour data itself (such as contour crossing, self-intersection, etc.) or deficiencies in the triangulation algorithm, such as incorrect facet orientation, facet distortion, etc. These erroneous faces will seriously affect the geometric accuracy and topological correctness of the model. Therefore, these erroneous triangles need to be manually checked and corrected. Correction methods include adjusting the connection relationship of the triangulated mesh, re-dividing the triangulated faces, and other operations to ensure that the triangulated mesh model can accurately and realistically reflect the original terrain and landform characteristics.

[0071] After the above editing and correction steps, the final accurate original geological model is obtained, such as Figure 1 The model is stored in the form of a triangular mesh, which accurately represents the surface morphology before the landslide occurs and provides a basis for subsequent landslide volume estimation and calculation model construction.

[0072] Furthermore, it also includes:

[0073] Step S2: obtaining post-landslide topographic data and constructing a post-landslide geological model representing the post-landslide geological state;

[0074] Step S2 is to obtain the surface morphological data after the landslide occurs and construct a high-precision post-landslide geological model to provide a basis for subsequent triangulation and landslide body identification. In this embodiment, drone photogrammetry technology is used to obtain the post-landslide terrain data.

[0075] Step 2.1: Use a drone equipped with an RTK high-precision positioning system to collect image data of the landslide area according to a preset route to obtain post-landslide terrain data;

[0076] In step 2.1, after a landslide occurs, a drone equipped with a high-precision RTK (Real-Time Kinematic) positioning system is quickly deployed to collect image data of the landslide area. RTK technology provides centimeter-level positioning accuracy, ensuring that the acquired image data contains highly accurate geographic coordinate information. Before data collection, a reasonable flight route must be pre-planned based on the scope and topographic characteristics of the landslide area, including parameters such as flight altitude, heading overlap ratio, and lateral overlap ratio to ensure the integrity and quality of the image data. The drone automatically flies and captures images along the pre-set route, acquiring high-resolution image data covering the entire landslide area, including oblique and orthophoto images. This image data contains information about the post-landslide surface morphology, such as the contours of the landslide body, the location of the sliding surface, and the collapse area.

[0077] Step 2.2, using photogrammetry technology to process the post-landslide terrain data to generate the post-landslide geological model, wherein the post-landslide geological model is a triangulated network model with a model accuracy reaching the centimeter level;

[0078] In step 2.2, after acquiring the drone image data, professional photogrammetry software, such as Pix4Dmapper, ContextCapture, or Smart3D, is used to process the image data and generate a post-landslide geological model. The photogrammetry processing process mainly includes the following steps:

[0079] The post-landslide terrain data is subjected to image stitching, geometric correction and three-dimensional reconstruction processing to generate the post-landslide geological model. Specifically, first, image stitching is performed to stitch multiple images taken by drones into a large-scale image mosaic to ensure the integrity and continuity of the image data. Then, geometric correction is performed to geometrically correct the image using the precise ground control point information provided by RTK technology to eliminate image distortion and improve the geometric accuracy of the image. Geometric correction includes the solution of internal orientation elements and external orientation elements of the image to ensure that the image has correct geographic coordinates and posture information. Finally, three-dimensional reconstruction technology, such as multi-view image dense matching algorithm (SGM, PMVS, etc.) or Structure from Motion (SfM) algorithm, is used to extract three-dimensional point cloud data from the geometrically corrected image data, and a triangulated network model is constructed based on the point cloud data to generate a post-landslide geological model. The generated post-landslide geological model is also a triangulated network model. Due to the use of high-precision RTK technology and advanced photogrammetry processing methods, the accuracy of the model can reach the centimeter level, which can finely reflect the surface morphology after the landslide occurs, such as Figure 2 shown.

[0080] Step S3, applying triangulated mesh carving technology to the original geological model to carve a carving model with a sliding surface;

[0081] Step S3, a core step of the present invention, utilizes triangulated mesh carving technology to simulate the removal of the landslide mass from the original geological model, creating a carved model with a sliding surface. This meticulous carving process accurately simulates the landslide mass's morphology and the location of the sliding surface, ensuring spatial consistency between the mesh nodes of the carved model and the original geological model at the sliding surface location. This facilitates subsequent landslide model construction and numerical simulation analysis.

[0082] Step 3.1, superimposing the post-landslide geological model on the original geological model;

[0083] In step 3.1, to accurately carve the triangulated mesh, the post-landslide geological model constructed in step S2 must first be superimposed on the original geological model constructed in step S1. In the 3D modeling software, both models are imported into the same coordinate system and spatially registered to ensure alignment. This superimposed model visually demonstrates the differences in surface morphology before and after the landslide. The post-landslide geological model indicates the extent and general morphology of the landslide mass, providing a reference boundary for subsequent carving operations.

[0084] Step 3.2, performing a triangulation operation on the original geological model with the landslide range indicated by the post-landslide geological model as the boundary;

[0085] In step 3.2, based on the model overlay, a triangulated mesh carving operation is performed on the original geological model, with the landslide range indicated by the post-landslide geological model as the boundary. Triangulated mesh carving technology is an interactive editing technology based on digital models, similar to carving on digital soil. In the present invention, a triangulated mesh carving tool, such as the carving function provided by software such as Geomagic Studio, ZBrush, or Blender, is used to perform local removal operations on the original geological model to simulate the sliding process of the landslide body. The boundary range of the carving operation is determined by the projection range of the post-landslide geological model on the horizontal plane, ensuring that the carving area is consistent with the actual landslide range.

[0086] Step 3.3, continuing the engraving operation until a sliding surface is revealed in the engraving area, stopping the engraving, and obtaining the engraving model;

[0087] In step 3.3, after determining the engraving range, continue the triangulation engraving operation and gradually remove the triangulation mesh of the original geological model in the landslide area. During the engraving process, it is necessary to refer to the morphological characteristics of the geological model after the landslide, such as the slope of the landslide body, the sliding direction, etc., and gradually adjust the engraving depth and direction to simulate the sliding trajectory of the landslide body. When the engraving area shows a clear sliding surface morphology, such as forming a smooth curved surface with a certain inclination angle, the engraving operation is stopped and the engraving model is obtained, such as Figure 3 and Figure 4 The carved model retains the topographic features of the original geological model outside the landslide area and forms a simulated sliding surface within the landslide area.

[0088] Step S3 further includes: when performing a triangulated mesh carving operation, controlling the carving depth and carving direction so that the mesh nodes of the sliding surface in the carving model and the mesh nodes of the original geological model at positions corresponding to the sliding surface are spatially overlapped;

[0089] Specifically, in order to ensure that the mesh nodes of the carving model and the original geological model at the sliding surface position maintain spatial position consistency, it is necessary to finely control the carving depth and carving direction when performing triangulated mesh carving operations. Specifically, during the carving process, it is necessary to monitor the position of the grid nodes in the carving area in real time and compare them with the mesh nodes at the corresponding positions of the original geological model. By adjusting the carving parameters, such as the size, strength, and direction of the carving brush, the mesh nodes of the sliding surface in the carving model are made to coincide with the mesh nodes at the corresponding positions of the sliding surface in the original geological model as much as possible in space. This node consistency ensures the topological connection relationship between the sliding surfaces of the two models, and provides accurate boundary conditions for subsequent set operations and numerical simulation analysis. In actual operation, the accuracy of node position consistency can be improved with the help of auxiliary functions such as node capture and grid alignment provided by the 3D modeling software.

[0090] Step S4, performing a set operation on the engraved model and the original geological model, extracting the difference parts, and forming a landslide model;

[0091] Step S4 aims to accurately extract the differences between the engraved model and the original geological model through set operations, thereby obtaining an independent landslide model. The landslide model contains the geometric shape and volume information of the landslide body, providing the final model data for subsequent landslide volume estimation and computational model construction.

[0092] Step 4.1, performing a Boolean difference operation on the engraved model and the original geological model to obtain a difference model including the landslide body;

[0093] In step 4.1, a Boolean difference operation is used to extract the differences between the engraved model and the original geological model. In the 3D modeling software, the engraved model is used as the subtracting object, and the original geological model is used as the subtracted object. This Boolean difference operation retains the portions of the original geological model that do not overlap with the engraved model and removes the portions of the original geological model that overlap with the engraved model. This results in a difference model that spatially corresponds to the region where the landslide was removed and contains the negative spatial information of the landslide.

[0094] Step 4.2: extracting from the difference model a portion that overlaps with the post-landslide geological model space as the landslide body model;

[0095] In step 4.2, the difference model obtained by the Boolean difference operation is actually the space where the landslide body is removed. In order to obtain a positive landslide body model, it is necessary to extract the part that overlaps with the post-landslide geological model space from the difference model. Specifically, a spatial intersection operation is performed on the difference model and the post-landslide geological model. The result of the intersection operation is to retain the part that the difference model and the post-landslide geological model occupy in space, and remove their respective non-overlapping parts. Since the difference model represents the space where the landslide body is removed, and the post-landslide geological model indicates the surface morphology after the landslide body slides, the intersection of the two just corresponds to the spatial range of the landslide body itself. After the intersection operation, an independent landslide body model is finally obtained, such as Figure 5 The model is stored in the form of a triangular mesh, which accurately represents the three-dimensional geometric shape of the landslide body and provides accurate model data for subsequent landslide volume estimation and computational model construction.

[0096] Following step S4, the method further includes step S5: calculating the volume of the landslide mass and constructing a landslide calculation model based on the landslide mass model for subsequent landslide stability analysis, landslide risk assessment, or landslide numerical simulation analysis. After obtaining the landslide mass model, calculating the volume of the landslide mass and constructing a landslide calculation model based on the model can be used in subsequent landslide engineering applications.

[0097] Furthermore, this embodiment also calculates the volume of the landslide body based on the above-mentioned landslide body model;

[0098] Specifically, the volume of a landslide is a crucial parameter for landslide hazard assessment and prevention engineering design. Based on the landslide model obtained in step S4, the volume of the landslide can be directly calculated. In 3D modeling software, the volume calculation function provided by the software, such as a triangular mesh-based volume integration algorithm, can be utilized to directly calculate the volume of the landslide model and obtain an accurate landslide volume estimate. Compared to traditional volume estimation methods based on two-dimensional topographic maps, the method of the present invention can fully utilize the three-dimensional geometric information of the landslide, improving the accuracy and reliability of volume estimation.

[0099] Furthermore, this embodiment also constructs a landslide calculation model based on the landslide body model for subsequent landslide numerical simulation analysis;

[0100] Specifically, the landslide calculation model is the basis for landslide stability analysis, risk assessment, and numerical simulation analysis. Based on the landslide body model obtained in step S4, a landslide calculation model for numerical simulation can be constructed. The landslide calculation model generally includes components such as a landslide body model, a sliding surface model, and a surrounding geological body model. In the method of the present invention, the landslide body model has been obtained in step S4, the sliding surface model can be extracted from the engraved model, and the surrounding geological body model can be expanded using the original geological model. By assembling and meshing these model components, a landslide calculation model for numerical simulation can be constructed.

[0101] Furthermore, the aforementioned numerical simulation analysis of landslides includes the use of finite element analysis (FEM) or discrete element analysis (DEM) to simulate and analyze stress distribution, displacement field changes, and potential hazardous areas during the landslide process. Specifically, after constructing a landslide calculation model, numerical simulation methods such as finite element analysis (FEM) or discrete element analysis (DEM) can be used to simulate and analyze the landslide process. Furthermore, FEM or DEM methods can be used to simulate and analyze stress distribution, displacement field changes, and potential hazardous areas during the landslide process.

[0102] Specifically, the finite element analysis method is suitable for simulating the deformation and destruction process of continuous media. It can discretize the landslide body and the surrounding geological body into a finite number of units. By solving the interaction forces between the units, the mechanical responses such as stress distribution and displacement field changes during the landslide process can be simulated. The discrete element analysis method is suitable for simulating the movement and destruction process of non-continuous media. It can discretize the landslide body into independent particles or blocks. By tracking the interaction between particles or blocks, the dynamic behaviors such as the motion trajectory and accumulation morphology of the landslide body can be simulated. In the numerical simulation analysis, the influence of external factors such as rainfall, earthquakes, and human activities can be considered to simulate the dynamic behavior of the landslide under different working conditions, evaluate the stability of the landslide, predict the movement trend and impact range of the landslide, and identify potential dangerous areas. Since the landslide calculation model constructed by the method of the present invention has grid node consistency at the sliding surface position, it can improve the accuracy and reliability of the numerical simulation and provide more scientific decision support for landslide disaster prevention and control.

[0103] The above description of the specific implementation method provides a clear understanding of the technical solution and implementation process of the method for estimating landslide volume and constructing a landslide calculation model, as described in the present invention. This method utilizes advanced drone photogrammetry and triangulation techniques to achieve high-precision and efficient landslide volume estimation and calculation model construction, providing strong technical support for landslide disaster prevention and control and engineering applications.

[0104] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A method for estimating the volume of a landslide and constructing a landslide calculation model, characterized in that: The following steps are involved: S1. Acquire geological data and construct an original geological model representing the geological state before the landslide; S2. Acquire post-landslide topographic data and construct a post-landslide geological model representing the post-landslide geological state; S3, applying triangulated mesh carving technology to the original geological model to carve a carving model having a sliding surface; S4, performing a set operation on the engraved model and the original geological model, extracting the difference parts, and forming a landslide model; Among them, the triangulated mesh carving operation in step S3 ensures that the grid nodes of the sliding surface in the geological model formed after carving maintain spatial position consistency with the grid nodes at the corresponding positions in the original geological model. Based on the landslide body model formed in step S4, the volume of the landslide body is estimated and a landslide calculation model is constructed.

2. The method for estimating landslide volume and constructing a landslide calculation model according to claim 1, characterized in that: In the step S1, it further includes: Step 1.1, collecting at least one of contour data, historical elevation data, and drilling data, or a combination thereof as the geological data; Step 1.2: Based on the collected geological data, an initial triangulated network model is generated using a triangulation algorithm; Step 1.3: Edit and modify the initial triangulated network model to obtain the original geological model.

3. The method for estimating the volume of a landslide and constructing a landslide calculation model according to claim 2, characterized in that: In step 1.3, also include: Manually correct erroneous triangular facets in the initial triangulated mesh model caused by data defects.

4. The method for estimating landslide volume and constructing a landslide calculation model according to claim 1, characterized in that: In the step S2, it further includes: Step 2.1: Use a drone equipped with an RTK high-precision positioning system to collect image data of the landslide area according to a preset route to obtain post-landslide terrain data; Step 2.2: Use photogrammetry technology to process the post-landslide terrain data and generate a post-landslide geological model. The post-landslide geological model is a triangulated network model with a centimeter-level accuracy.

5. The method for estimating landslide volume and constructing a landslide calculation model according to claim 4, characterized in that: In step 2.2, it also includes: The post-landslide terrain data is processed through image stitching, geometric correction and 3D reconstruction to generate a post-landslide geological model.

6. The method for estimating landslide volume and constructing a landslide calculation model according to claim 1, characterized in that: The step S3 further includes: Step 3.1, superimposing the post-landslide geological model on the original geological model; Step 3.2, performing a triangulation operation on the original geological model with the landslide range indicated by the post-landslide geological model as the boundary; Step 3.3: Continue the engraving operation until a sliding surface is revealed in the engraving area, then stop engraving to obtain the engraving model.

7. The method for estimating landslide volume and constructing a landslide calculation model according to claim 6, characterized in that: The step S3 further includes: When performing triangulated mesh carving operations, the carving depth and carving direction are controlled so that the mesh nodes of the sliding surface in the carving model and the mesh nodes of the original geological model at positions corresponding to the sliding surface are spatially overlapped.

8. The method for estimating landslide volume and constructing a landslide calculation model according to claim 1, characterized in that: In the step S4, it further includes: Step 4.1, performing a Boolean difference operation on the engraved model and the original geological model to obtain a difference model including the landslide body; Step 4.2: Extract the portion that overlaps with the post-landslide geological model space from the difference model as the landslide body model.

9. The method for estimating landslide volume and constructing a landslide calculation model according to claim 8, characterized in that: After step S4, the method further includes step S5: Based on the landslide body model, landslide body volume calculation is performed and / or a landslide calculation model is constructed for subsequent landslide stability analysis, landslide risk assessment or landslide numerical simulation analysis.

10. The method for estimating landslide volume and constructing a landslide calculation model according to claim 9, characterized in that: The numerical simulation analysis of landslide includes simulating and analyzing the stress distribution, displacement field changes and potential dangerous areas during the landslide process using finite element analysis or discrete element analysis methods.

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