Granular micromechanics approach (GMA) provides a predictive theory for granular material behavior by connecting the grain-scale interactions to continuum models. Here, we have used GMA to predict the closed-form expressions for elastic constants of macroscale chiral granular metamaterial. It is shown that for macroscale chirality, the grain-pair interactions must include coupling between normal and tangential deformations. We have designed such a grain-pair connection for physical realization and quantified with FE model. The verification of the prediction is then performed using a physical model of 1D bead string obtained by 3D printing. The behavior is also verified using a discrete model of 1D bead string.

中文翻译：

---

颗粒微力学预测的手性超材料：用增材制造合成的一维示例进行验证

颗粒微力学方法（GMA）通过将晶粒间相互作用与连续模型联系起来，为颗粒材料的行为提供了一种预测理论。在这里，我们已经使用GMA预测了宏观手性粒状超材料的弹性常数的封闭形式。结果表明，对于宏观手性，晶粒对相互作用必须包括法向和切向变形之间的耦合。我们设计了这样的颗粒对连接用于物理实现，并使用有限元模型进行了量化。然后使用通过3D打印获得的1D珠串的物理模型执行预测的验证。还使用一维珠串的离散模型验证了该行为。