Assessment of printing direction in flexural tests of 3D printed reinforced concrete beams

In Brazil, research on 3D-printed mortar remains nascent, with limited progress in structural applications. In this context, the present study aims to evaluate the structural impact of the printing direction on 3D-printed mortar beams. The study compares three types of beams: those printed in the longitudinal direction, those printed in the transverse direction, and conventionally cast beams. All beams were longitudinally reinforced and subjected to flexural testing. As anticipated, the cast beams exhibited superior strength compared to the beams printed with layers oriented longitudinally along the beam's axis. Beams printed with layers in the transverse direction demonstrated a significant reduction in strength, attributed to weakened interlayer bonding, creating preferential crack propagation paths.