摘要
提出一种用于结构多尺度有限元建模与分析的部分混合单元法,实现整体宏观模型与局部精细化模型边界条件的直接传递.将宏观模型的一部分附加建立到精细化模型的周边,该部分单元外侧边界节点的相对坐标与宏观模型一致,从而根据节点坐标对应施加整体分析获得的节点力或节点位移;该部分单元内侧边界的低维度单元与精细化模型的高维度单元之间采用多点约束或基于面约束的线-面接触单元连接,以保证不同尺度模型在界面的变形协调.通过组合梁算例分析表明：部分混合单元法的位移计算结果与目标解精确符合,应变计算结果在断面中心处误差为0.3%～4.4%,在断面侧边缘局部小范围最大误差约7.9%,该方法相对于整个结构的多尺度混合单元模型,在保证计算精度的同时,大大减轻了建模工作量和计算成本.
A partial mixed finite element method for multi-scale modeling and analysis was proposed, so the boundary conditions could be transferred from global model to refined finite element model directly. To establish a segment of global model by surrounding of the refined finite element model, the relative coordinates of outer boundary nodes of these elements were consistent with the global model, so the nodal forces or nodal displacements calculated from global model could be applied corresponding to coordinate locations. The inner boundary of lower dimension element of partial global model was connected with higher dimension element of refined finite element model using multi-point constraint or line to surface contact element supporting surface-based constraint mode, so the deflection consistent at interface of different scale model could be assured. A composite beam was taken as analysis object, and results show that the calculated displacements of partial mixed finite element method are in good agreement with the exact solution, as well as the error of the calculated strains is about 0.3%-4.4% at the center of the section, and the maximum error is about 7.9% at the edge of the section. Compared with the multi-scale mixed finite element model of the whole structure, the modeling workload and computational cost of the proposed method are greatly reduced, while the same calculation accuracy can be obtained.
作者
伍彦斌
黄方林
Wu Yanbin;Huang Fanglin(School of Civil Engineering, Central South University, Changsha 410075, China)
出处
《华中科技大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2018年第5期110-114,共5页
Journal of Huazhong University of Science and Technology(Natural Science Edition)
基金
贵州省交通运输厅科技资助项目(2013-122-001)
关键词
多尺度有限元分析
边界条件
混合单元法
线-面接触单元
组合结构
multi-scale finite element analysis
boundary condition
mixed finite element method
line to surface contact element： composite structure
