Juxtaposing fresh material characterisation methods for buildability assessment of 3D printable cementitious mortars

Both industry and academia are rapidly developing processes, materials, projects to explore the potential of extrusion-layering additive manufacturing cementitious generally known as 3D concrete printing (3DCP). Because lack supportive formwork makes objects prone failure during printing, a key aspect remains so-called ‘buildability’, qualitative descriptor indicate resistance against such failures. Obviously, material characteristics applied print mortar an important (although not sole) parameter determine buildability. However, it is yet clear which properties most suitable, how they should be determined experimentally. In literature, range approaches has been suggested, but comparative studies very few in number limited scope. This paper presents juxtaposition fresh characterisation methods by subjecting four different mortars tests related buildability, including rotational rheometry, unconfined uniaxial compression tests, direct shear ultrasonic wave transmission tests. For reference, some hardened state were also determined, trial was performed on one mixture. Significant differences between mixtures found, development characteristics, even though three composed proportions same 4 dry materials. Furthermore, shown that strength values from experiments could only correlated assuming significant friction angles associated with Mohr-Coulomb behaviour. We propose this established relatively easily through novel method, combining rheometry-shear test results. The data seem would valid approach. Normalized physically parameters, compressive pulse velocity, consistently correlated. Their time mixture-dependent, adds complexity quality control generalized characterize compare buildability mortars.