A new three-dimensional mesh modeling method for geological bodies containing complex faults in geological engineering

WenLi Gao ^* Xinming Lu Shengzhe Hou Tianyu Zhang Wenting Liu

• Shandong University of Science and Technology, Qingdao, China

Three-dimensional geological modeling and visualization hold considerable significance for both application and research across various fields, including \color{blue}geosience, marine geology, environmental protection, mining engineering, and geological engineering.However, the technique and approach are exposed to critical challenges for complex geological bodies, including heightened structural complexity, extensive manual intervention, and diminished accuracy of discontinuity surfaces \color{red}owing \color{blue} to the presence of faults, particularly conflicting discontinuity surfaces generated by reverse faults. In this paper, a novel technical workflow \color{red}and \color{blue} a set of three-dimensional structure modeling methods for geological bodies containing complex faults \color{red}were \color{black} designed. \color{black}A model stitching strategy based on \color{red}the ear clipping algorithm was proposed to incorporate fine fault models into the modified original model. This strategy transforms the integration of complex three-dimensional models into a triangulation problem for simple two-dimensional polygons, ensuring topologically consistent and computationally efficient merging. Simultaneously \color{black}, a contour \color{red}line segments \color{black} sorting algorithm based on \color{red}a \color{black} vertex sequence \color{red}was \color{black} proposed to accelerate the extraction of boundary contour \color{red}line segments\color{black}. \color{blue}We used a two-stage detection strategy to accelerate locating overlap regions. \color{black} A multi-layer triangulated irregular network-3DT model was constructed through continuous stratum modeling, fine fault modeling, overlap detection based on the two-dimensional projection topological relationship, extraction of ordered contour line segments of model boundaries, \color{red}and \color{black}model reconstruction based on \color{red}the \color{black} ear \color{red}clipping \color{black}. \color{red}An \color{black} underground modeling \color{red}experiment revealed \color{black} that \color{red}these \color{black} modeling methods and technical systems can accurately depict the geometric form around complex geological faults. \color{red}A \color{blue} quantitative and qualitative comparison between the proposed modeling method and various modeling methods demonstrates that our method is superior in flexibility, robustness, and mesh quality. \color{black}