Particle-bed 3D printing in concrete construction – Possibilities and challenges

This article provides an overview of different particle-bed 3D printing techniques for the production of concrete elements. A classification is proposed which considers the direct production of concrete components, the production of formwork as well as composite components by means of a permanent formwork. Three techniques are considered as relevant for concrete construction, i.e. selective binder activation, selective paste intrusion and binder jetting. Design as well as material aspects are addressed. The underlying physics of fluid infiltration into the particle-bed and its effect on the properties of the hardened material are discussed on the basis of recent research results. Finally, the first applications of particle-bed 3D printing are presented which demonstrate the potential of this technique in concrete construction.