On optimizing crash energy and load-bearing capacity in cellular structures
On optimizing crash energy and load-bearing capacity in cellular structures
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DOI：
10.1016/j.ijsolstr.2007.08.001
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发表时间：
2008-01
影响因子：
3.6
通讯作者：
H. Chai
中科院分区：
文献类型：
--
作者：
H. Chai
研究了几种模型蜂窝结构在轴压作用下的能量吸收和承载能力，并考虑了基于结构质量或可变形体积的优化问题。三种配置被认为是：多层，多细胞和多管，所有的矩形细胞的拓扑结构。平行或垂直于单元轴施加载荷。细胞的纵横比和材料的相对密度ρ系统地变化。试样的横向约束刚性壁稳定的变形，但限制的效果减少了足够大的细胞数量。正方形单元拓扑结构似乎是最佳的。与适当的ρ值一起，这提供了对特征屈曲的波长的最佳约束，从而提供了贯穿材料主体的广泛的能量耗散。当同时考虑平均应力、压碎能和基于最小质量和体积的冲程或致密化应变时，ρ ε 0.5似乎是冲突趋势中可行的折衷。在这种情况下，机械性能相对于普通蜂窝状结构（对于普通蜂窝状结构，ρ通常<0.1）显著改善。
The energy absorption and load-bearing capacity under axial compression of some model cellular structures are studied with an eye toward optimization based on structural mass or volume available for deformation. Three configurations are considered: multilayer, multi-cell and multi-tube, all of a rectangular-cell topology. Loading is applied either parallel or normal to the cell axis. The cell’s aspect ratio and the relative density of the material ρ are systematically varied. The specimens are laterally confined by rigid walls to stabilize the deformation, but the effect of confinement diminishes for sufficiently large number of cells. A square-cell topology seems to be optimal. Together with an appropriate value for ρ, this provides an optimal constraint on the wavelength of the characteristic buckle and consequently extensive energy dissipation throughout the material body. When considering mean stress, crush energy and stroke or densification strain on the basis of minimum mass and volume simultaneously, ρ≈0.5 seem to be a viable compromise among conflicting trends. The mechanical performance in this case is considerably improved over common cellular structures, for which ρ is typically <0.1.