A Concentric Ring Architecture Inspired by Tree Growth Rings for Flax Epoxy Woven Composites

This preprint presents a multiscale finite element analysis of flax/epoxy woven composites. At the microscale, a parametric study investigates the influence of fiber volume fraction, yarn spacing, yarn fiber volume fraction, and fabric thickness on the effective elastic properties of plain and twill weave laminae. At the macroscale, a bio-inspired concentric ring architecture based on the growth rings of a tree trunk is proposed and benchmarked against conventional 0° and quasi-isotropic flat laminates under tensile and bending loadings. The concentric ring configuration consistently exhibits lower peak stress and maximum deformation than the flat laminates. These findings provide structural insights that may inform the future development of natural fiber composites for load-bearing applications. This is a preprint and has not been peer-reviewed.