Biochar addition for 3DCP: a preliminary study

This contribution presents the first results of an ongoing research aimed at highlighting the possible reduction in the environmental impact of concrete through the synergy between two interconnected strategies: the exploitation of by-products, in this case biochar, for the realization of 3D printable cementitious conglomerates. Thanks to the use of biochar, the mixes presented are characterized by an excellent dimensional stability in the fresh state, evaluated through the extrusion test. Regarding the hardened state properties, the contribution highlights the effects of biochar-to-cement ratio, water-to-cement ratio (in combination with biochar content) and sand-to-cement ratio on the flexural and compressive strength of the mixes. The evaluation of CO2 emissions shows that a proper mix design could result in a significant reduction in CO2 emissions (up to 43%) while maintaining good mechanical performance (compressive strength of at least 60 MPa).