SUITABILITY TESTS FOR 3D PRINTING WITH CEMENTIOUS MORTARS

Additive manufacturing has found widespread application across various industrial sectors including the construction industry, which presents significant potential. Nonetheless, the utilization of materials for 3D-printed construction encounters challenges due to their unique properties, particularly their setting time. Hence, a thorough investigation into the rheology of 3D-printed mortar becomes imperative.

The material used for this process must exhibit a delicate balance, being sufficiently fluid to facilitate smooth transportation through the pump pipe while also possessing the requisite viscosity to support multiple layers when applied. Furthermore, the 3D-printed filament must feature a smooth surface and continuity to ensure optimal cohesion between layers. To assess these properties, three key criteria are established: pumpability, extrudability, and buildability.

This study aims to investigate the methodology for measuring these characteristics. Two complementary testing methods are employed: simple standard tests for construction materials providing an estimation of rheological characteristics and rheometer tests ensuring precise and reliable measurements of yield stress and viscosity. The primary objective lies in identifying a suitable test methodology for assessing the rheological traits of materials on the construction site. Various tests, including the flow table test, fall cone test, V funnel test and pistol test, are compared to determine the optimal approach for predicting the suitability of cementitious material for 3D printing. Experimental assessments conducted by means of the RheoCAD rheometer are indispensable for comprehending material behaviors across diverse testing conditions.