Investigation of the equivalent mechanical properties of the bone-inspired composite cellular structure: Analytical, numerical and experimental approaches

This study investigated the development of an analytical model using the energy method and Castigliano's second theory to evaluate the equivalent mechanical properties for a bone-inspired cellular structure of a glass fiber-reinforced Polylactic Acid (PLA) composite material. The bone-inspired cellular structure was fabricated using a Fused Deposition Modeling (FDM) 3D printing technique. The fabricated specimens were subjected to compression testing. The digital image correlation technique was employed for obtaining stain and displacement contours in experimental tests. Furthermore, a finite element numerical model was developed to evaluate the mechanical properties of the bone-inspired composite cellular structure. The comparison of the experimental and numerical results with the outcomes of analytical model revealed that the proposed analytical model can correctly determine the mechanical properties of the composite bio-inspired cellular structure. The results showed that by reinforcing the cellular structure with continuous fiber, significantly higher mechanical properties can be obtained. A comprehensive parametric study has also been performed to investigate the effect of geometric parameters on equivalent mechanical properties.