小麦茎秆的抗弯复合材料力学模型

Composite Mechanics Model of Wheat Stalk under Bending

为研究小麦茎秆的抗弯性能和获得茎秆材料常数,本文首先对小麦茎秆进行了四点弯曲的试验研究。在试验测量数据的基础上建立了小麦茎秆有限元计算模型,该模型考虑了植物材料的正交异性和管壁分层力学参数的变化等情况。本文还将Brazier屈曲理论引入小麦茎秆抗弯性能研究中,使用双层复合材料圆柱壳模型,分析得到了纯弯曲时小麦茎秆的曲率弯矩关系。研究结果表明:理论模型能够正确反映小麦茎秆的抗弯行为;局部屈曲是影响小麦茎秆的抗弯性能的重要因素;试验和有限元计算结果与理论解基本吻合。

To invesigate the bending characteristics and obtain material properties of wheat stalk, four-point bending tests were performed. A finite-element model of wheat stalk was established, where the orthotropic and layered mechanical characters were considered. Brazier buckling theory was also introduced to simulate wheat stalk bending cylindrical double-layered composite shells model, which perfectly demonstrate the bending behaviors.