Enrico Dini is the founder of D-Shape, pioneers in large-scale 3D printing using concrete-like materials. They've developed a technique for solidifying sand into a kind of sandstone using a chlorine-based fluid.
The 3D printer is truly massive and must be erected on the building site - or else you'd better hire trucks and cranes to move the massively heavy 3D prints.
Printing is done using a standard powder-style process: a flat layer of sand has the liquid binder dribbled upon it. Another layer of dry sand is applied and the process repeats. Eventually the print completes and then loose, unbound sand must be removed. Although we haven't seen the process in person, we suspect there's quite a bit of manual labor involved in operating this printer - but that's an opportunity for future improvement.
Dini's implementations so far include several massive sculptures and, strangely, artificial reefs in Bahrain.
The possibilities for use of D-Shape are huge, since construction can make use of the same benefits as have the parts industry. For example, the interior of concrete blocks can be 3D printed with strong but light lattices - impossible using conventional building approaches. Unusual geometries also become feasible.
One has to think big when considering D-Shape's technology, as they apparently have been doing, if this image is accurate.