纵向载荷下作物茎秆"挠曲线"的变化特征测试与分析

摘要：以"非完善压杆"为作物茎秆的力学模型,应用力学理论,分析了纵向载荷下茎秆挠度与影响作物茎杆倒伏的各种因素间的关系。用简易测量装置对3个不同品种的小麦茎秆在不同纵向载荷下的"挠曲线"进行了测量。通过对相关测试数据的科学分析表明,作物茎秆"挠曲线"的形状变化是诸多因素作用的结果,"挠曲线"的坐标物理意义明晰、测量方便、操作简单,可用来评价作物抗倒性。并从理论和试验两方面证明了其评价作物抗倒性的合理性。该研究可为抗倒伏研究和相关农业机械的设计提供参考。

Measurement and analysis on "deflection curve" variation characters of crop-stem under axial loading

Taking "non-ideal column" as mechanical model of the crop stem, crop-stem deflection and the relationships between influencing factors of crop-stem lodging were analyzed under axial loading with mechanical theories. The "deflection curve" for stems of three wheat cultivars under different axial loadings were measured with a simple equipment, then relative testing data was analyzed scientifically. The results indicated that shape changing of crop-stem deflection curve was caused by many factors and coordinates of "deflection curve" had the obvious physical meaning, was easy to measure and simple to operate. The coordinates of "deflection curve" could be used to evaluate the lodging resistance. In this article, its reasonability to evaluate lodging resistance was proved both theoretically and experimentally. This research further provides references for crop lodging resistance research and related agricultural machine designing.