Method For Mesh Generation Of High-Quality Tetrahedral Meshes Of Complex Geological Model

Numerical simulation has become an indispensable method for solving scientific problems and conducting scientific research,and the high-quality computational mesh of complex geological models is the key to analyzing rock and soil deformation and failure.Experience has shown that high-quality meshes can accelerate the convergence time of numerical simulation and ensure the accuracy of calculation simulation.It is very difficult to divide different strata into high-quality meshes with different sizes because of the complex geometry of 3D geological model.At the same time,there are a large number of tetrahedral meshes in 3D geological models,and the optimization of mesh division is also relatively difficult.Therefore,the research and implementation of high-quality tetrahedral meshing method for complex geological models has always been one of the popular topics.In this paper,an adaptive algorithm for high quality tetrahedral mesh generation is proposed.At the same time,a bubble mesh algorithm based on K-means clustering algorithm for high-quality tetrahedral mesh generation of complex geological model is proposed.Finally,the two methods are applied to engineering examples to verify the feasibility of the methods and realize high-quality tetrahedral mesh generation of complex 3D geological model.The main research work of this paper is as follows:(1)A high quality tetrahedral and adaptive mesh generation algorithm for complex 3D geological model is proposed.The algorithm can generate high quality tetrahedral meshes from topologically consistent surface meshes.On the CGAL platform,with the help of the programming tool visual studio community 2017,the high-quality tetrahedral mesh adaptive generation of complex 3D geological model is realized.At the same time,taking a complex 3D geological model as an example,the algorithm is applied to generate high-quality tetrahedral mesh.(2)A bubble meshing method based on K-means clustering algorithm is proposed.The clustering algorithm is applied to cluster analysis on the surface mesh of the geological model,and the surface points are grouped according to the clustering results to configure the internal initial bubbles.The high-quality point set is generated through the interaction force and the motion control equation,and the tetrahedral meshes is generated using the constrained Delaunay triangulation algorithm.Finally,high-quality computational meshes were generated through finite element mesh merging.(3)Taking a slope model in Shanxi Province as an example,two tetrahedral meshing methods were carried out.The quality analysis of the meshes proved that the generated computational meshes were high-quality and the meshes were used for numerical calculation.Through the mesh quality metrics of volume-to-edge ratio,skewness,aspect ratio,orthogonality,face angle,dihedral angle,the quality of the tetrahedral elements were analyzed.Analyzing the proportion of different quality elements,it proves that the quality of the meshes were very high.The high-quality computational meshes were imported into FLAC^3D for numerical calculation through the developed interface,which shows the practicality and effectiveness of the generated computational meshes.