Effect of Different Expansive Agents on the Early-Age Structural Build-Up Process of Cement-Paste (2023-09)¶

Recent advances in additive manufacturing have enabled the design and fabrication of auxetic materials with programmable geometries and tailorable properties, but ongoing challenges remain in integrating them for composite design. In this work, we exploit a composite design strategy on cementitious material units embedded with three-dimensional re-entrant (3DR) lattices fabricated by single and dual material printing. Guided by experimental tests, the effect of additive manufacturing parameters on the mechanical properties of rigid and flexible 3DR lattices is confirmed. Then, we characterize the compressive behavior of lattice-reinforced cementitious composite (LRCC) units embedded with 3DR lattices printed using rigid, flexible, and dual materials with various spatial distributions. We found comparable ultimate strengths and higher energy-absorbing capabilities despite weaker 3D-printed materials embedded in LRCC units. A similar observation was found on LRCC columns with various geometric patterns. We envision that our proposed composite design strategy can produce next-generation low-carbon material systems with high performance and production efficiency toward a sustainable built environment.