考虑坝基复杂地形的堆石坝三维有限元网格自适应生成方法OA

To address the key problems in 3D finite element mesh generation for rockfill dams with complex dam foundation topography—such as difficulties in fitting the boundaries between different material zones and filling stages,controlling the meshes of the transition zone between the dam body and foundation,and accurately represent-ing the excavation boundaries—an adaptive 3D finite element mesh generation method for rockfill dams is proposed.The method employs element transformation to adaptively fit complex boundaries of material zones and filling stages.A transition factor for the meshes of the dam body and foundation is constructed using fractal theory to control the rate of element size variation and adaptively generate the foundation transition zone.A rigorous terrain cutting surface fit-ting algorithm for 3D meshes is developed based on a chained dimension-reduction scheme of"body-face-edge-vertex",enabling the generation of a 3D dam foundation mesh that accurately reflects the excavation surface.Statisti-cal analyses of mesh quality indicators—including aspect ratio,parallel deviation,maximum angle,and Jacobian ratio—for the 3D meshes of five dams generated using this method demonstrate that the method is featured by control-lable overall mesh quality meeting the shape quality requirements for subsequent finite element analysis,and signifi-cantly improved efficiency of 3D modeling.This method enables adaptive generation of rockfill-dam finite element meshes from 2D maximum cross sections to 3D finite element models,providing an efficient and reliable preprocess-ing approach for refined numerical simulation of rockfill dam body-foundation systems with complex dam foundation topography.