Out-of-plane elastic constants of curved cell walls honeycombs

Abstract

The work describes the out-of-plane properties of a curved wall honeycomb structure evaluated using analytical models and finite elements techniques. Out-of-plane properties are calculated using a theoretical approach based on energy theorems and validated using a full-scale finite element technique to simulate transverse shear tests. The effects of the curvature of the walls and the depth of the honeycomb cells on the out-of-plane elastic constants are evaluated and excellent agreement is observed between theoretical and numerical models. These curved cell wall honeycombs feature specific (i.e., relative density weighted) highly tailorable upper shear bounds that shift their maximum values with the radiuses of the curved cell walls at different internal cell angles. Finally, it is also shown that these honeycombs exhibit a particular topology with a specific upper boundary independent of the non-zero curvature cell wall adopted and only dependent upon the internal cell angle.