Abstract

Miura-ori core sandwich structures are promising substitutes to conventional honeycomb core sandwich structures for both load bearing and multifunctional applications. While quasi-static or impact behaviors have been widely studied, no theoretical work has been done yet for free vibration analysis of carbon-fiber-reinforced Miura-ori core sandwich beams (MSBs). This paper presents a simple and effective methodology to investigate the free vibration behavior of MSBs under simply supported boundary conditions. The governing equation of motion is built by Hamilton’s principle. Carbon-fiber-reinforced Miura-ori core is transformed to a continuous homogeneous material and the analytical expression of its equivalent transverse shear modulus is derived based on an energy approach. According to the deformation contributions of different components and shear modulus analysis of Miura-ori core, the differences of natural frequencies between the theoretical prediction and numerical simulation are analyzed. It indicates that the analytical model presented in this paper is effective to estimate the natural frequencies of carbon-fiber-reinforced MSBs, which may provide some references for further practical engineering applications of such kinds of composite sandwich structures.

摘要

Miura-ori 夹芯结构是传统蜂窝夹芯结构的有希望的替代品，可用于承重和多功能应用。虽然准静态或冲击行为已被广泛研究，但尚未对碳纤维增强 Miura-ori 芯夹层梁 (MSB) 的自由振动分析进行理论工作。本文提出了一种简单有效的方法来研究 MSB 在简支边界条件下的自由振动行为。运动的控制方程是由汉密尔顿原理建立的。将碳纤维增强三浦织芯转化为连续均质材料，基于能量法推导出其等效横向剪切模量的解析表达式。根据Miura-ori岩心不同组分的变形贡献和剪切模量分析，分析了理论预测与数值模拟的固有频率差异。表明本文提出的解析模型对估计碳纤维增强MSB的固有频率是有效的，可为此类复合夹层结构进一步的实际工程应用提供一定的参考。