Biochar-Infused 3D Concrete Printing for Carbon Sequestration (2026-03)¶

3D Concrete Printing (3DCP) is a transformative advancement in the building industry that is poised to increase efficiency, reduce labor and waste, and be more resilient to natural disasters. 3DCP utilizes automated layerby-layer additive manufacturing techniques that can accelerate construction timelines and enhance architectural design flexibility. Despite its benefits and recent advancements, 3DCP technology still has many challenges, including the high carbon footprint mainly attributable to its carbon-intensive nature on cement-based mixtures. Reducing the embodied carbon of cement-based materials employed in 3D printing is crucial to the building industry. This study proposes an innovative strategy to add locally produced biochar to 3DCP mixes to reduce the overall carbon footprint. The biochar, a carbon-rich material used in this study, is generated through the pyrolysis of an agricultural byproduct, corn stover, and added into 3D printable concrete mixtures. A lifecycle assessment (LCA) adhering to ISO 14040 and ISO 14044 standards was performed to investigate the decarbonization capacity of biochar. The results indicated a notable reduction in carbon emissions, with an emission factor of -1.954kgCO2/kg, suggesting that each gram of biochar added effectively compensates for about two grams of carbon dioxide emissions linked to cement production. Structural tests conducted by our research team, following the ASTM C39 and C293 standards, showed that biochar-infused 3DCP mix can achieve sufficient compressive and flexural strength. All things considered, integrating locally produced biochar is expected to substantially mitigate carbon emissions in the 3DCP process.