Multiscale analysis of natural fiber biocomposites using representative volume elements

In recent years, the demand for sustainable engineering materials has driven increased interest in bio-composites, which are hybrid materials composed of natural fibers and/or bio-based polymers. Modeling techniques, particularly those based on representative volume elements (RVEs), have emerged as powerful tools to investigate the behavior of these composite systems. This study presents a multiscale finite element method (FEM) analysis of hybrid bio-composites reinforced with natural and synthetic fibers using a three-dimensional (3D) RVE approach. A numerical RVE is proposed to simulate a unidirectional composite microstructure consisting of pineapple leaf, jute, and E-glass fibers embedded in epoxy, polylactic acid (PLA), and biobased polyethylene terephthalate (BioPET) matrices. The RVE was designed to reflect the spatial distribution and volume fractions of each fiber type, with FEM simulations performed in Abaqus/Standard using periodic boundary conditions to extract homogenized elastic and shear properties. The obtained results revealed pronounced anisotropy in the composites’ mechanical behavior, driven primarily by fiber alignment and material properties. E-glass fibers excelled in stiffness and load-bearing capacity along the longitudinal direction, while natural fibers provide secondary reinforcement, particularly in transverse and shear loading conditions. PLA outperformed BioPET in stiffness and interfacial shear strength, closely matching epoxy’s performance. Parametric studies on fiber substitution (nettle, bagasse, abaca) further demonstrated the critical role of fiber type and location within the composite architecture. These findings highlight the utility of RVE simulations in sustainable composite design and optimizing hybrid configurations for structural applications.