汽车防撞栏仿竹薄壁管结构的能量吸收特性

ENERGY ABSORPTION CHARACTERISTIC OF BIOMIMETIC BAMBOO THIN⁃WALLED TUBE STRUCTURE FOR CAR CRASH BARRIERS

基于竹子的宏观、微观结构特征,提出了两种仿竹结构:带加强节的变壁厚薄壁管结构(Tube⁃a)和双圆带肋的仿竹薄壁管结构(Tube⁃b)。借助Abaqus工具对仿生结构在三点弯曲加载下的吸能特性进行了研究,并引入了常规圆管结构做对比分析。结果表明,Tube⁃b的表现最佳,其峰值破碎力较圆管结构降低了约18.396%,其比吸能和吸能效率分别提升了约50.8%、38.797%。为进一步研究仿竹结构的吸能特性,探讨了加载角度、壁厚属性α及截面属性β等参数对Tube⁃b能量吸收特性的影响。发现在0°~20°载荷下,Tube⁃b的综合性能表现较佳;适当调节壁厚属性,可以提高Tube⁃b的吸能效率;适当调节截面属性,可以提高Tube⁃b的比吸能。该研究可为改善薄壁结构能量吸收特性的设计提供一定参考。

Based on the macroscopic and microscopic structural characteristics of bamboo,two bionic bamboo structures were proposed:a thin⁃walled tube with variable wall thickness with reinforcing joints(Tube⁃a)and a thin⁃walled bamboo⁃like tube with ribs in a double circle(Tube⁃b).The energy absorption characteristics of the bionic structures under three⁃point bending loading were investigated with the help of Abaqus tool,and the conventional circular tube structure was introduced for comparative analysis.The results show that Tube⁃b has the best performance,its peak crushing force is reduced by about 18.396%compared with the circular tube structure,and its specific energy absorption and energy absorption efficiency are improved respectively by about 50.8%and 38.797%.To further investigate the energy absorption characteristics of the bamboo⁃like structure,the effects of parameters such as loading angle,wall thickness propertyαand cross⁃section propertyβon the energy absorption characteristics of Tube⁃b were explored.It is found that the comprehensive performance of Tube⁃b is better under 0°~20°loading;the energy absorption efficiency of Tube⁃b can be improved appropriately by adjusting the wall thickness property,and the specific energy absorption of Tube⁃b can be improved appropriately by adjusting the cross⁃section property.This study can provide some references for the design of improving the energy absorption characteristics of thin⁃walled structures.