Formulation of extrudable mortar

The main objective of this study is to formulate an extrudable mortar. To achieve this goal, an experimental approach was adopted to optimize the mix design and improve the flow behavior of the fresh mortar, ensuring continuous and homogeneous extrusion. Several formulations were tested with a cylindrical extruder, varying the proportions of sand, fibers and superplasticizer. The study showed that fibers reduce flowability and increase water demand compared with non-fibrous mortars. Fibers also improve mix cohesion, which in turn improves mortar extrudability. Moreover, excessive sand content induces frictional behavior in the mix. Increasing the superplasticizer dosage from 1% to 3% allowed for a reduction in water content and enabled extrusion without water migration at low speed. Finally, extrusion speed was identified as a critical parameter for ensuring process success.