Evaluating Glass Powder Substitution for 3D Printed Concrete (2026-01)¶

The construction industry faces increasing pressure to reduce its environmental footprint through improved materials and construction practices. This study investigates the use of ultra-fine glass powder (UFGP) as a partial cement replacement in reactive powder concrete (RPC) for 3D-printed concrete (3DPC), focusing on thermal performance and embodied carbon reduction. Six mix designs with UFGP replacement levels up to 25% were evaluated. Experimental results show that substituting 5% of cement with UFGP reduces thermal conductivity by 10.9%, enhancing the material’s insulation capacity. EnergyPlus simulations for a residential building in Shanghai indicate a potential annual energy savings of 2.6 MJ/m² (4.85%) with 5% UFGP-enhanced concrete, arising from the synergistic effects of reduced thermal conductivity and increased thermal mass. Although the high binder content (1000 kg/m3) remains a limitation of current 3DPC technology, partial cement replacement with UFGP presents a viable strategy for lowering embodied carbon while improving thermal performance. These results demonstrate the potential of UFGP to advance next-generation sustainable construction by enhancing energy efficiency and reducing embodied carbon in 3D-printed concrete applications. However, further investigation is needed to validate performance across a wider range of environmental and structural conditions.