Novel Modeling Technique of Metamaterials Using One-Dimensional Finite Elements

Geometry-driven metamaterials offer negative Poisson’s ratios, vanishing shear stiffness, and programmable multi-stability, but their slender struts and large rotations overwhelm conventional finite-element meshes. A streamlined framework that couples classical finite elements with the Carrera Unified Formulation (CUF) resolves cross-sectional deformation through higher-order beam expansions, reproducing three-dimensional behaviour while retaining a one-dimensional model. Contrary to the conventional beam definition, in this study the structural beam axis is aligned with the thickness of the sandwich panel, while the cross-section extends across its width. This particular application is useful to highlight the flexibility of CUF in modelling any structural configuration as an advanced 1D element. Representative static linear analyses are presented of the hexagonal metamaterial design.