Alternative Printing-Methods for Cementitious Materials (2025-01)¶

Robotic concrete construction goes beyond the technique of depositing successive layers or filaments, which then solidify. In the field of construction materials, 3D printing technologies are multiple and not limited to extrusion 3D printing. Spatial resolution and absolute freedom of form can be achieved by alternative 3D printing techniques. In their fresh state, cementitious materials are subject to Newton's first law, and all the problems encountered during extrusion stem from the force of gravity. Alternative techniques are suitable for creating honeycomb shapes, but also with reservations (voids in the structure), where ducts can pass through. In particular, these ducts can be used for post-tensioning reinforcement. An alternative technique for achieving functional gradation within the material appears to be already in use with foams. Indeed, graduated porosities are included in concretes by incorporating different quantities of foaming agents. These studies pave the way for exploiting alternative techniques for greater functionality in buildings.