The D-Shape®’s building process is a patented method that involves three main phases: a CAD/CAE phase, a CAM phase and a FINISH phase.
The CAD/CAE Phase – The building structure can be designed with any commercial 3D CAD (Computer Aided Design) Program. The resulting 3D graphic file gives the physical and mechanical properties of the 3D printed material, subject to structural Finite Element Analysis (FEM) and possible topological optimization through the use of various commercial CAE (Computer Aided Engineering) Programs. When there is a satisfactory structure optimization for the different load and thermal conditions provided, the graphic file is exported in the standard STL (Stereo Litho Graphy) format and uploaded in the computer of the 3D Printer. Designers should be well aware about the nature of the D-Shape® process and apply some simple but fundamental design rules. According to our patented method, the building file is enveloped and merged into the 3D file containing the Shell (a thin ephemeral shell to be demolished at the end of the process) and the resulting 3D file is given to our slicing proprietary software, Monolite®. This will horizontally partition the building in slices a few millimeters thick from the bottom to the top, making it ready for the print, layer by layer.
The CAM Phase – By pressing the command ‘Print’ on our Supervisor HMI (Human Man Interface), the D-Shape® starts the construction process: a first layer of aggregates (sand, gravel, or any other mix) will be spread out by the Spanning Gantry to form a layer of uniform thickness, ready to write on. Our binder jetting print head is set in motion and selectively deposits the binding agent only in the full areas of the building. At the end, the entire frame is raised according to the printing pitch. These operations are repeated in an orderly manner for all layers until the process reaches the end. During the layering process you can stop and add horizontal reinforcements, such as rods and nets, to give strength to the ceilings, before resuming printing. One night’s worth of curing will be sufficient to begin the Finish phase on the freshly-printed structure, that will be hidden in its shell. Thanks to the homebuilt shell, the printer can be moved alongside the structure, from where it can proceed immediately to the next printing session.
The FINISH phase – The unbound granular material is removed with powerful vacuum cleaners, unveiling the structure. The removed granular material is then recycled in the next print. As soon as the granular material level starts to decrease, the workers can start plastering the walls and mount the electrical and plumbing. If the designer has provided appropriate cavities and traces in the walls, these operations will be very rapid. If the designer has provided vertical cavities, then vertical re-bars can be added in the structure to further strengthen the building. At the end the thin ephemeral shell is demolished. The shell can be partitioned into slabs to be used for paving or crushed and recycled.