Mechanically robust lattices inspired by deep-sea glass sponges

The predominantly deep-sea hexactinellid sponges are known for their ability to construct remarkably complex skeletons from amorphous hydrated silica. The skeletal system of one such species of sponge,Euplectella aspergillum, consists of a square-grid-like architecture overlaid with a double set of diagonal bracings, creating a chequerboard-like pattern of open and closed cells. Here, using a combination of finite element simulations and mechanical tests on 3D-printed specimens of different lattice geometries, we show that the sponge's diagonal reinforcement strategy achieves the highest buckling resistance for a given amount of material. Furthermore, using an evolutionary optimization algorithm, we show that our sponge-inspired lattice geometry approaches the optimum material distribution for the design space considered. Our results demonstrate that lessons learned from the study of sponge skeletal systems can be exploited for the realization of square lattice geometries that are geometrically optimized to avoid global structural buckling, with implications for improved material use in modern infrastructural applications. Computational analysis and mechanical testing demonstrate that the skeletal system of a marine sponge has, through the course of evolution, achieved a near-optimal resistance to buckling.

Automated summary

Computational analysis and mechanical testing have shown that the skeletal system of deep-sea hexactinellid sponges has achieved near-optimal resistance to buckling through evolution. The diagonal reinforcement strategy of the sponge achieves the highest buckling resistance for a given amount of material, and the sponge-inspired lattice geometry approaches the optimum material distribution for the design space considered. Lessons learned from studying sponge skeletal systems can be applied to geometrically optimize square lattice structures to avoid global structural buckling and improve material use in modern infrastructural applications.