Directional mechanical properties and wave propagation directionality of Kagome honeycomb structures

Abstract

Abstract This paper deals with in-plane mechanical properties of periodic honeycomb structures with orthotropic Kagome cells and wave propagation in this Kagome honeycomb. Effective directional elastic stiffness, initial yield and elastic buckling strength of these honeycombs under in-plane compression and shear are derived in analytical forms. The directional mechanical properties of the Kagome structures are associated to two geometrical parameters describing the configuration of the cell, i.e., the relative density and the shape anisotropy-ratio. For varying values of these two parameters, very good agreement is found between the predictions of the effective stiffness obtained by the analytical expressions and the numerical calculations based on the mathematical homogenization method for the same orthotropic Kagome cell. Optimum design of the orthotropic Kagome cells is investigated for maximum stiffness and strength. While the wavelength of the wave is larger than the size of the unit cell of the Kagome honeycomb structure, the Kagome structure behaves as an equivalent medium with the effective orthotropic properties. The wave propagation directionality of orthotropic Kagome honeycomb structures is discussed via several numerical examples.