This study presents a novel approach to designing low-carbon cementitious composites by integrating nature-inspired topologies and hybrid binder systems. Leveraging 3D-printed triply periodic minimal surface (TPMS) formworks made from recyclable Polylactic Acid (PLA) material, two-phase cementitious composites are fabricated using high-performance cementitious (HPC) mortar and geopolymer mortar (GPM). Two configurations are investigated: one with cement-based mortar as the outer part and geopolymer as the core part (HG) and the other with the reverse arrangement (GH). Mechanical tests, including uniaxial compression and direct tension, are conducted on individual mortars and composite cubes. Experimental results demonstrate that the HG configuration exhibits superior mechanical performance and enhanced ductility compared to GH, owing to the confinement effect of the outer high-performance mortar. Finite element simulations using a simplified concrete damage plasticity model can capture internal stress distribution and damage evolution, validating experimental observations. This TPMS design strategy enables performance optimisation through functional grading and highlights the potential of hybrid material systems for achieving mechanical efficiency and sustainability in cementitious composites.
Nguyen-Van et al. (Mon,) studied this question.