Additive manufacturing of low-carbon concrete : by-product based and alkali activated mixes for sustainable construction

Abstract

Additive manufacturing for concrete, 3D concrete printing, has attracted attention in construction and research projects worldwide. This technology involves building structures using concrete printed layer by layer. The construction industry adopted 3D concrete technology due to the advantages it offers including freedom in geometry, low cost, formwork- free, less human intervention, and safety. The concrete used in this technology has a strict requirement to achieve printability such as flowability, extrudability, and buildability. The common solution is to increase the percentage of the cement in the mixture to meet these requirements. As a result, the cement content needed for 3d concrete is higher than in conventional concrete which limits the sustainability of this technology. The University of Malta addresses this issue through two distinct studies aimed at enhancing the sustainability of 3D concrete printing. [excerpt]