Bio-inspired 3D-printed earthen materials and structures

Nature provides a powerful blueprint for fabricating high-performance 3D-printed earthen materials and structures, such as termite mounds, wasp nests, and honeycomb worm reefs. However, mimicking the chemical and biological building blocks nature employs remains largely unexplored at scale. Here, we introduce a multiscale, bio-inspired approach that optimizes physicochemical interactions between biopolymers and earthen minerals at the microscale and systematically scales preferred interactions across spatial dimensions to fabricate macroscale, high-performance, 3D-printed earthen structures. By analyzing 90% of global subsoil minerals, we established a universally applicable multiscale optimization pathway, which converged on an alginate-based biopolymer-stabilizer that increases printing speeds by 33% and structural stability by 10° in architecturally relevant structures. This discovery accelerates the development of more efficient, resilient, and complex 3D-printed earthen structures, paving the way for sustainable, high-performance construction in the 21st century.