关于蜂窝芯体面外等效剪切模量的讨论

对于六边形蜂窝芯体，其面内等效参数具有确定的解析式，便于应用；相比之下，对于面外等效剪切模量，现有工作只能给出其上下限，由于没有确定的取值，给工程计算带来了困扰。为克服这一矛盾，本文通过Y型蜂窝胞元，针对薄面板的情况，重新分析了芯材的面外等效剪切模量。针对直壁板与斜壁板厚度为1:1和2:1的情况，给出了近似的弹性力学解答，并由此确定出面外等效剪切模量的上限。本方法所确定的剪切模量的上限与文献给出的剪切模量的下限是相同的，从而使该模量也具有确定的解析表达式，方便了数值计算和分析。试验数据和有限元数值分析均验证了本文结论的正确性。

THE DISCUSSION ON EQUIVALENT TRANSVERSE SHEAR MODULUS OF HONEYCOMB CORES

The equivalent in-plane elastic moduli of hexagonal honeycombs have determinate solution. Compared to the in-plane properties, only the lower and upper bounds are obtained for equivalent transverse shear modulus. Due to the lack of determinate solution, it will bring many troubles for practical engineering applications. For this reason, this paper deals with the calculation of the transverse shear modulus of a honeycomb sandwich panel, under the influence of the thin face panel. Based on the Y-shaped representative unit cell, then the upper bound of hexagonal honeycomb is obtained when the ratio of the thickness of central wall to inclined wall is 1:1 and 2:1. The result shows that it is equal to the lower limit of Gibson and Kelsey’s formula. Finally, both the experimental data and finite element analysis show that the proposed theoretical solution can predict the equivalent shear modulus of honeycomb cores with good accuracy.