ABSTRACT
3D printing of concrete (3DPC) is a lineage technology of additive manufacturing (AM) that has transitioned from early industrial applications in the aerospace, medical and automobile sectors to recent explorations in academia and the construction industry. Recent interest in 3DPC can be ascribed to its comparative advantage regarding cost, material waste, labour and time reductions. Moreover, 3DPC enables the free-form construction of complex geometries, increased customisation and the use of various construction materials. Notwithstanding current development, many 3DPC projects still only showcase the feasibility of this novel technology but cease to portray an essential correlation between theoretical and practical application. For this to realise a fundamental comprehension of the print process particularities concerning the unique material properties of the printed object is required. In this research, a novel thixotropy model for the characterisation of cement-based materials shows that SiC nanoparticles improve 3D printability by enhancing thixotropy. The experimental investigation demonstrates that nanoparticle-infused cement-based materials improve the mechanical performance and inter-layer bond strength (IBS) of 3D printed objects. Scanning electron microscopy (SEM) images are presented to illustrate the microscopic morphology of a cement paste’s microstructure due to nanoparticle addition. Finally, validation 3D printed objects depict the improvements in buildability.
