竹材跨尺度数值模拟与非对称弯曲性能研究

Multiscale Numerical Simulation and Asymmetric Bending Behavior of Bamboo

摘要:

提出了一种针对竹材非均匀多孔复合结构的跨尺度数值模拟方法。通过耦合细观代表性体积单元（RVE）建模与宏观有限元分析，系统揭示了竹材非对称弯曲的内在机制：构建了包含多孔梯度特征的代表性体积单元（P-RVE）模型；采用渐进均匀化理论量化了其等效弹性参数；并通过非对称弯曲实验验证了宏观模型的可靠性；通过离散化重构薄壁组织与维管束的空间拓扑关系，不仅实现了对竹材横截面正交异性特征的参数化表征，还成功实现了跨尺度模拟。

Abstract:

A multiscale numerical simulation approach for the heterogeneous porous composite system of bamboo was proposed. By coupling mesoscale representative volume element （RVE） modeling with macroscopic Finite Element Analysis， it systematically revealed the intrinsic mechanism of asymmetric bending in bamboo material. First， a porosity gradient-informed RVE （P-RVE） model was constructed to characterize microstructural characteristics. Second， Asymptotic Homogenization Theory was employed to quantify equivalent elastic parameters. Finally， asymmetric bending experiments validated the reliability of the macroscopic model. Results demonstrate that discrete reconstruction of the spatial topology between parenchyma tissue and vascular bundles not only enables parametric characterization of cross-sectional orthotropic features but also facilitates successful cross-scale simulation.