In 3D printing, also known as additive manufacturing, components are built by printing layers on top of each other until the structure is complete. Structures start as digital models in CAD environments and are translated into a machine-readable code. In civil engineering, additive manufacturing is an emerging technology, and one that offers several benefits: it can reduce construction time, reduce waste and offers a high degree of architectural freedom. Extrusion-based 3D printing methods are said to be the most promising in civil engineering [1] and are thus the focus of current developments. Researchers have identified the major influences ...