Generation of 3D finite element mesh of layered geological bodies in intersecting fault zones

Abstract

As the geological fault surface divides the 3D space of stratified ores and rocks into complex spatial surface domains, it is necessary to fully consider the spatial relationship between intersecting fault zones and geological bodies in the process of 3D modeling, and how to accurately establish the 3D finite element mesh of geological bodies in intersecting fault zones is a difficult point in modeling complex geological structure. The laminated geological body in intersecting fault zone is a multifaceted domain grid model consisting of a ground-level grid, a geological fault plane grid, and a range grid. By analyzing the spatial relationship between the geological interfaces of the intersecting fault zones, a closed manifold processing method is proposed to establish the closed manifold spatial surface model of the intersecting fault zones, based on which the closed spatial surface model is tetrahedrally divided to establish a 3D solid model. Finally, the 3D solid model is imported into Ansys to generate a 3D finite element mesh. VC++ is used as the development platform for programming, to realize the generation and closed manifold processing of ground level and geological fault surfaces, and use TetGen library to generate finite element mesh based on irregular tetrahedron. Taking an intersecting fault zone in an open-pit mine as an example, the 3D finite element mesh of laminated geological bodies in the intersecting fault zone is established successfully. This method provides an effective and feasible solution for generating accurate 3D finite element meshes in complex stratigraphic spaces based on closed manifold processing.