The effect of node bond adhesive fillet on uniaxial in-plane responses of hexagonal honeycomb core

In the present work, experimental and numerical studies were conducted on the in-plane uniaxial behavior of a fiberglass/phenolic honeycomb core to investigate the effects of the node bond adhesive fillet. A non-linear finite element model (FEM) with large displacements of the repetitive unit cell of the hexagonal cell honeycomb core is employed to study the in-plane behavior numerically. The model was used to conduct a parametric study on the effects of the adhesive fillet and its geometry. To validate the numerical model, a series of in-plane quasi-static tensile and compressive tests was carried out. Numerical analysis showed that increased node bond adhesive fillet size significantly induces higher tangent stiffness of the honeycomb core. Good agreement was observed between the model predictions and test results. Analytical models from the literature without adhesive or adhesive fillet were also used for comparison.