Zhang Shuang, Mu Zhengzhi, Song Wenda, Zhang Zhiyan, Yu Hexuan, Zhang Binjie, Han Zhiwu, Ren Luquan
Key Laboratory of Bionic Engineering, Ministry of Education, Jilin University, Changchun 130022, China.
Institute of Structured and Architected Materials, Liaoning Academy of Materials, Shenyang 110167, China.
Biomimetics (Basel). 2024 Dec 26;10(1):6. doi: 10.3390/biomimetics10010006.
Slender tubes are in high demand owing to their lightweight and outstanding energy absorption. However, conventional slender tubes are prone to catastrophic failures such as Euler's buckling under axial load. Interestingly, growing bamboos overcome this similar dilemma via a unique tapered intine in the internodes, which endows them with excellent energy absorption. Inspired by this finding, a bionic inner-tapered tube (BITT) was designed to enhance the energy absorption of slender tubes under axial load. The special energy absorption (SEA) was evaluated via a quasi-static axial compression test. Then, theoretical calculation and finite element analysis were carried out to analyze the energy absorption mechanisms. The results reveal that the tapered inner wall induces a progressively enhanced fold deformation mode for BITT, which not only prevents buckling failure and decreases initial peak crushing load but also improves the energy absorption efficiency by increasing plastic deformation. The influences of taper and length-diameter ratio on the axial energy absorption of BITT are explored. Finally, the bionic square array (BSA) and bionic hexagon array (BHA) are fabricated by taking BITT as the basic structural unit, which significantly improves the main energy absorption performance indicators under axial load.
细长管因其轻质和出色的能量吸收能力而有很高的需求。然而，传统的细长管在轴向载荷下容易发生灾难性故障，如欧拉屈曲。有趣的是，生长中的竹子通过节间独特的锥形内壁克服了类似的困境，这赋予了它们出色的能量吸收能力。受这一发现的启发，设计了一种仿生内锥形管（BITT），以增强细长管在轴向载荷下的能量吸收能力。通过准静态轴向压缩试验评估了特殊能量吸收（SEA）。然后，进行了理论计算和有限元分析，以分析能量吸收机制。结果表明，锥形内壁为BITT诱导了一种逐渐增强的折叠变形模式，这不仅防止了屈曲失效，降低了初始峰值挤压载荷，还通过增加塑性变形提高了能量吸收效率。探讨了锥度和长径比对BITT轴向能量吸收的影响。最后，以BITT为基本结构单元制作了仿生方形阵列（BSA）和仿生六边形阵列（BHA），显著提高了轴向载荷下的主要能量吸收性能指标。
