A method for constructing a dynamic three-dimensional geological model of GIS-MPM seamless integration
The dynamic 3D geological model construction method with seamless integration of GIS-MPM solves the problem that traditional 3D geological modeling cannot handle complex and variable analysis needs, realizes dynamic display and efficient calculation, and supports the simulation of complex geological processes.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- CHONGQING GEOLOGY & MINERAL EXPLORATION & DEV BUREAU NANJIANG HYDROGEOLOGY ENG GEOLOGY TEAM
- Filing Date
- 2022-08-29
- Publication Date
- 2026-07-21
AI Technical Summary
Traditional 3D geological modeling methods cannot effectively handle the variability of spatial and temporal data structures, and cannot meet the complex and ever-changing analytical needs of engineering applications.
The dynamic 3D geological model construction method with seamless integration of GIS-MPM is adopted. DEM layers are generated by interpolation of borehole data imported into ArcGIS platform, a hexahedral spatial grid is established and material points are arranged. The deformation of rock and soil is calculated by combining the material point method and adaptive technology, and the 3D solid geological model is updated in real time.
It enables dynamic display and high-precision calculation and analysis of three-dimensional geological models, simulates large deformation processes of rock and soil, improves the calculation efficiency and flexibility of the model, and supports geological disaster simulation.
Smart Images
Figure CN115392032B_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of three-dimensional geological modeling technology, and in particular relates to a method for constructing dynamic three-dimensional geological models with seamless integration of GIS and MPM. Background Technology
[0002] Three-dimensional geological modeling is one of the core technologies for next-generation geological surveys and deep resource exploration, and it is also an important foundation for geological spatial analysis, geological phenomenon interpretation, and geological process simulation. However, current research on three-dimensional geological modeling is in a stage of gradual development from static models to dynamic models. The static display, measurement, statistics, and analysis functions of traditional three-dimensional geological models cannot effectively handle the variability of spatial and temporal data structures, and cannot meet the complex and ever-changing analytical needs of engineering applications.
[0003] Meanwhile, various numerical simulation methods are gradually being applied to geological work. These methods can quantitatively calculate and analyze complex physical processes. Integrating suitable numerical simulation methods for simulating large deformations of rock and soil masses into three-dimensional geological models can greatly improve the models' computational analysis capabilities and dynamic simulation capabilities, giving them true "life." Therefore, establishing a dynamic three-dimensional geological model construction method by combining advanced numerical simulation theory has significant practical implications and application value for enhancing the models' computational analysis and dynamic simulation capabilities. Summary of the Invention
[0004] In view of the above-mentioned deficiencies of the prior art, the purpose of this invention is to provide a GIS-MPM seamless integration dynamic three-dimensional geological model construction method to solve the shortcomings of traditional static modeling methods.
[0005] To achieve the above objectives, this invention provides a method for constructing a dynamic three-dimensional geological model with seamless integration of GIS and MPM, comprising the following steps:
[0006] 1) Import the borehole data into ArcGIS, and interpolate the borehole points of each stratum in the geostatistical analysis module to obtain the elevation raster data layer (i.e., DEM layer) of each stratum;
[0007] 2) In the DEM map of each stratum, the center point of each grid cell is used as a node. After horizontal connection, a quadrilateral cell grid is formed. The corresponding nodes are vertically connected between strata and appropriately divided to generate a hexahedral spatial grid. This spatial grid is not used for calculation, but only for arranging the spatial position of material points.
[0008] 3) Arrange an appropriate number of material points in each spatial grid in a regular manner, and mark the stratigraphic number to which each material point belongs. At the same time, the material points are trimmed according to the scope of the study area.
[0009] 4) A regularly arranged cubic background grid covering the entire computational domain, which is used for material point method calculations;
[0010] 5) Import the soil and rock parameter data of each stratum into ArcGIS, and generate a soil and rock parameter raster data layer for each stratum. Extract the soil and rock parameter data of each raster unit of each stratum and assign the values to all material points belonging to that stratum below the raster unit, including density, internal friction angle, cohesion, elastic modulus, Poisson's ratio, tensile strength, etc.
[0011] 6) Set the initial conditions, boundary conditions, and load conditions for the material point model;
[0012] 7) Calculate the deformation of soil and rock masses using the material point method;
[0013] 8) After each material point method calculation is completed, for the new spatial distribution of material points, traverse all material points belonging to the stratum below each grid cell of each stratum, find the material point with the largest elevation, use the elevation of the material point to cover the original elevation data of the grid cell, and at the same time add the calculation results of the material point, including stress, strain, displacement, velocity and other data, to the grid cell.
[0014] 9) After each step of the material point method calculation is completed, the updated local stratum elevation raster data is used in ArcGIS to generate a three-dimensional solid geological model in real time by constructing a triangular network. At the same time, different colors are used to represent the magnitude distribution of the calculated results such as stress, strain, displacement, and velocity.
[0015] As an optimization, in step 7), the material point method is fully integrated into the GIS platform as a custom tool script. The calculation process for each time step is as follows: map the physical quantities stored at the material point to the background grid nodes. Solve the momentum equation on the background grid. Map the solved physical quantities back to the material point and update the motion state of the material point.
[0016] As an optimization, in step 7), the material point adopts an adaptive technique. When the equivalent length of the material point in a certain direction satisfies the condition of equation (1), the material point is split into two along that direction, and the mass and volume are halved after the split.
[0017]
[0018] In the formula, mp is the mass of the substance point, ρ0 is the initial density of the substance point, and Δt is the calculation time for each step. Let be the volumetric strain rate at each step, α be the splitting factor, and d be the background mesh spacing.
[0019] As an optimization, in step 7), the background mesh adopts an adaptive technique. When the strain energy of the background mesh satisfies the condition of equation (2), the mesh is divided into four parts, and all material points within it are split simultaneously.
[0020]
[0021] In the formula, n is the number of background grids containing material points, Ω is the computational domain, and Ω i Let σ be the computational domain of the background mesh i, σ be the stress tensor, D be the strain tensor, and η be the given allowable splitting coefficient.
[0022] As an optimization, in step 7), the soil and rock mass adopts the DP constitutive model, and the model yield function is shown in equations (3) and (4):
[0023]
[0024]
[0025] In the formula, f s with f t Let I1 be the yield function, J2 be the first invariant of the stress tensor, and σ be the second invariant of the deviatoric stress tensor. t For tensile strength, parameters α and k can be derived from cohesion c and the angle of internal friction. Sure.
[0026] As an optimization, after step 9), it also includes changing different soil and rock parameters, initial conditions, boundary conditions and load conditions, repeating the steps, and dynamically updating the three-dimensional solid geological model according to the different soil and rock deformation calculation results.
[0027] The technical effects of this invention are beyond doubt:
[0028] A. Seamlessly integrating GIS and MPM fully leverages the advantages of GIS in 3D modeling and visualization technology, as well as the advantages of MPM in computational analysis and dynamic simulation, thereby enabling the 3D geological model to have dynamic display capabilities.
[0029] B. The material point simulation method overcomes the numerical difficulties caused by mesh distortion when simulating large deformations of rock and soil using the traditional finite element simulation method, and can better simulate geological disasters such as landslides and collapses;
[0030] C. By utilizing adaptive techniques for material points and background meshes, the mesh and material points are automatically refined in regions with large strain, providing good flexibility and ensuring both computational accuracy and efficiency.
[0031] D. All calculation processes are implemented on the GIS platform through secondary development, including the conversion of DEM to material point model and the conversion of material point model to three-dimensional solid geological model, which can be completed automatically on the GIS platform.
[0032] The geotechnical parameters, initial conditions, boundary conditions, and load conditions can be adjusted arbitrarily in the model, thereby obtaining different dynamic responses of the three-dimensional geological model based on different simulation results. Attached Figure Description
[0033] Figure 1 The implementation method flowchart.
[0034] Figure 2 The elevation raster data layer is shown in the example.
[0035] Figure 3 This is a schematic diagram of the method for generating material points.
[0036] Figure 4 This is the material point calculation model in the embodiment.
[0037] Figure 5 This is the initial three-dimensional geological model used in the example.
[0038] Figure 6 The example shows a three-dimensional geological model at 2 seconds. Detailed Implementation
[0039] The present invention will be further described below with reference to the accompanying drawings and embodiments. It should be noted that in the description of the present invention, terms such as "upper," "lower," "left," "right," "inner," and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. These terms are used only for the convenience of describing the present invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific manner. Therefore, they should not be construed as limitations on the present invention. Terms such as "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.
[0040] See Figure 1 This embodiment discloses a method for constructing a dynamic three-dimensional geological model with seamless integration of GIS and MPM, including the following steps:
[0041] 1) Organize the borehole data and import it into ArcGIS. In the geostatistical analysis module, interpolate the borehole points of the strata to obtain a strata DEM layer with a resolution of 1m × 1m, such as... Figure 2 As shown;
[0042] 2) In the stratigraphic DEM map, using the center point of each grid cell as a node, horizontal lines are connected to form a quadrilateral cell grid. Corresponding nodes are then vertically connected between strata and appropriately divided to generate a hexahedral spatial grid, such as... Figure 3 As shown;
[0043] 3) Arrange an appropriate number of material points regularly within each spatial grid, and label each material point with its corresponding stratigraphic number. Simultaneously, trim the material points according to the study area to form a material point computational model, such as... Figure 4 As shown, the model dimensions are 200m * 200m * 100m, and the number of matter points is 402,391. The density of the matter point arrangement will affect the accuracy of the calculation results.
[0044] 4) Arrange a cubic background grid for calculation covering the entire calculation area. The background grid size is selected as 1m×1m×1m. The density of the background grid will affect the accuracy of the calculation results.
[0045] 5) Import the strata and soil parameters data into ArcGIS, and generate a raster data layer of soil parameters for each stratum. Extract the soil parameters data of each raster unit of each stratum and assign them to all material points belonging to that stratum below the raster unit, including density, internal friction angle, cohesion, elastic modulus, Poisson's ratio, tensile strength, etc.
[0046] 6) Given the initial conditions, boundary conditions (fixed boundary, symmetric boundary, etc.) and load conditions (gravity load, structure load, etc.) of the material point model, set the time step size for each calculation step. The time step size for each calculation step must be less than the maximum critical step size to ensure calculation convergence.
[0047] 7) The material point method is used to calculate the deformation of soil and rock masses. This method is fully integrated into the GIS platform as a custom tool script. The calculation process for each time step is as follows: Map the physical quantities stored at the material point to the background grid nodes. Solve the momentum equation on the background grid. Map the solved physical quantities back to the material point and update the motion state of the material point.
[0048] The material point adopts an adaptive technique. When the equivalent length of the material point in a certain direction satisfies the condition of equation (1), the material point is split into two along that direction, and its mass and volume are halved after splitting.
[0049]
[0050] In the formula, mp is the mass of the substance point, ρ0 is the initial density of the substance point, and Δt is the calculation time for each step. Let be the volumetric strain rate at each step, α be the splitting factor, and d be the background mesh spacing.
[0051] Meanwhile, the background mesh also adopts an adaptive technique. When the strain energy of the background mesh satisfies the condition of equation (2), the mesh is divided into four parts, and all material points within it are split:
[0052]
[0053] In the formula, n is the number of background meshes containing material points, Ω is the computational domain, Ωi is the computational domain of background mesh i, σ is the stress tensor, D is the strain tensor, and η is the given allowable splitting coefficient.
[0054] The soil and rock mass adopts the DP constitutive model, and the model yield function is shown in equations (3) and (4):
[0055]
[0056]
[0057] In the formula, fs and ft are yield functions, I1 is the first invariant of the stress tensor, J2 is the second invariant of the deviatoric stress tensor, and σ t For tensile strength, parameters α and k can be derived from cohesion c and the angle of internal friction. Sure.
[0058] 8) After each material point method calculation is completed, for the new spatial distribution of material points, traverse all material points belonging to the stratum below each grid cell of each stratum, find the material point with the largest elevation, use the elevation of the material point to cover the original elevation data of the grid cell, and at the same time add the calculation results of the material point, including stress, strain, displacement, velocity and other data, to the grid cell.
[0059] 9) After each step of the material point method calculation is completed, a three-dimensional solid geological model is generated in real time in ArcGIS using the updated local stratigraphic elevation raster data and by constructing a triangulation network, such as... Figure 5 and Figure 6 As shown, the dynamic changes of the constructed three-dimensional geological model are illustrated, and the colors of the triangular mesh in the figure represent the distribution of horizontal displacement values.
[0060] 10) Change different soil and rock parameters, initial conditions, boundary conditions and load conditions, repeat the steps, and dynamically update the three-dimensional solid geological model according to the different soil and rock deformation calculation results.
[0061] 11) This embodiment integrates GIS and MPM seamlessly through secondary development, making up for the shortcomings of traditional static modeling methods. It provides an effective way to improve the quantitative calculation and dynamic display capabilities of three-dimensional geological models and has certain practical application value.
[0062] The preferred embodiments of the present invention have been described in detail above. It should be understood that those skilled in the art can make numerous modifications and variations based on the concept of the present invention without creative effort. Therefore, all technical solutions that can be obtained by those skilled in the art based on the concept of the present invention through logical analysis, reasoning, or limited experimentation on the basis of existing technology should be within the scope of protection defined by the claims.
Claims
1. A method for constructing a dynamic three-dimensional geological model with seamless integration of GIS and MPM, characterized in that, Includes the following steps: 1) Import the borehole data into ArcGIS, and interpolate the borehole points of each stratum in the geostatistical analysis module to obtain the elevation raster data layer of each stratum, which is the DEM layer. 2) In the DEM map of each stratum, the center point of each grid cell is used as a node. After horizontal connection, a quadrilateral cell grid is formed. The corresponding nodes are vertically connected between strata and appropriately divided to generate a hexahedral spatial grid. This spatial grid is not used for calculation, but only for arranging the spatial position of material points. 3) Arrange an appropriate number of material points in each spatial grid in a regular manner, and mark the stratigraphic number to which each material point belongs. At the same time, trim the material points according to the scope of the study area. 4) A regularly arranged cubic background grid covering the entire computational domain, which is used for material point method calculations; 5) Import the soil and rock parameter data of each stratum into ArcGIS, and generate a soil and rock parameter raster data layer for each stratum. Extract the soil and rock parameter data of each raster unit of each stratum and assign the values to all material points belonging to that stratum below the raster unit, including density, internal friction angle, cohesion, elastic modulus, Poisson's ratio and tensile strength. 6) Set the initial conditions, boundary conditions, and load conditions for the material point model; 7) Calculate the deformation of soil and rock masses using the material point method; 8) After each material point method calculation is completed, for the new spatial distribution of material points, traverse all material points belonging to the stratum below each grid cell of each stratum, find the material point with the largest elevation, use the elevation of the material point to cover the original elevation data of the grid cell, and at the same time add the calculation results of the material point, including stress, strain, displacement and velocity data, to the grid cell. 9) After each step of the material point method calculation is completed, the updated local stratum elevation raster data is used in ArcGIS to generate a three-dimensional solid geological model in real time by constructing a triangular network. At the same time, different colors are used to represent the magnitude distribution of the stress, strain, displacement, and velocity calculation results.
2. The method for constructing a dynamic three-dimensional geological model with seamless GIS-MPM integration as described in claim 1, characterized in that, In step 7), the material point method is fully integrated into the GIS platform in the form of a custom tool script. The calculation process for each time step is as follows: map the physical quantities stored on the material point to the background grid nodes; solve the momentum equation on the background grid; map the solved physical quantities back to the material point and update the motion state of the material point.
3. The method for constructing a dynamic three-dimensional geological model with seamless GIS-MPM integration as described in claim 1, characterized in that, In step 7), the material point adopts an adaptive technique. When the equivalent length of the material point in a certain direction meets certain conditions, the material point is divided into two along that direction, and the mass and volume are halved after the split.
4. The method for constructing a dynamic three-dimensional geological model with seamless integration of GIS-MPM as described in claim 3, characterized in that, In step 7), the background mesh adopts an adaptive technique. When the strain energy of the background mesh meets certain conditions, the mesh is divided into four parts, and all material points within it are split.
5. The method for constructing a dynamic three-dimensional geological model with seamless GIS-MPM integration as described in claim 1, characterized in that, In step 7), the soil and rock mass adopts the DP constitutive model.
6. The method for constructing a dynamic three-dimensional geological model with seamless GIS-MPM integration as described in claim 1, characterized in that, After step 9), the process also includes changing different soil and rock parameters, initial conditions, boundary conditions, and load conditions, repeating the steps, and dynamically updating the three-dimensional solid geological model based on the different soil and rock deformation calculation results.