Investigation into quasi-static compressive behaviors of several kinds of honeycomb like structures in three axial directions

The natural bees' honeycombs maintain long-term structural stability in harsh environments, employing a highly material-efficient approach. However, the reasons remain somewhat ambiguous. To clarify the stabilization mechanism and investigate quasi-static compression responses of double-layer ordered cellular structures, honeycomb, Tóth and single-layer cellular structures with a relative density (ρr) of 25.84% were fabricated using 3D printing technology. Then, quasi-static compression experiments in three directions were conducted. Further, a numerical study was conducted to uncover the stabilization mechanism and effect of ρr on compressive behaviors. Results revealed that the stabilization mechanism was mainly attributed to bearing load priority of intermediate layer and its inhibition on formation of plastic hinges. A relative density of 5.17% served as a transition point for deformation mode, beyond which honeycomb and Tóth structures exhibited stronger in-plane compressive strength at expense of less sacrificed out-of-plane compressive strength, below which they both exhibited more stable compressive curves compared to single-layer cellular structures, which were favorable for energy absorption. This study clarifies the stability mechanism of bees' honeycombs and addresses the lack on compression behaviors of double-layer ordered cellular structures. Moreover, it introduces two available bionic structures with controllable deformation modes to expand the application of single-layer cellular structures.