3D Printing, or Additive Manufacturing, is a range of machine technologies that share one same principle –adding small bits of material on top of each other to create objects. This is usually done layer by layer, which means that the final object is created by stacking a series of different layers one on top of another. Each layer has its unique shape and is placed in the exact order, similarly to sliced bread, where each layer continuously follows the next one. This process allows for very complex objects to be simplified by dividing them into as many two dimensional layers as necessary.
The process starts from a virtual 3D model made on a computer, which is sliced into layers through dedicated software. Each layer is then translated into the instruction code for the printer that tells it how to move and drop material in order to create each one of those layers. The printing of a layer is typically done by pushing, or extruding, a melted or fluid material through a pipe, called nozzle, while it is moving across the printable area. This creates a continuous line of material that deposits onto the printable surface and hardens, creating the layer. The next layer is printer right on top of the first one, which acts as the support surface for the second. Very often the two layers don’t match completely, and the layer on top risks having areas with no support surface, because there is a void underneath it. In those cases, a temporary support structure is printed with the layer below, just to support the layers coming above, and later removed when the printing process is finished. The whole process is repeated until all the layers have been printed, starting from the bottom one and reaching the top of the object.
There has certainly been some crucial software development that radically changed the tools we use in designing our buildings and structures (first CAD - Computer Aided Design, and now BIM - Building Information Modeling), but the act of physically creating them has essentially stayed the same for thousands of years. While other industries have adopted and integrated automation into their processes, construction remains a very manual, labor-intensive industry. This often translates into poor health and safety conditions, extremely limited form freedom (complex shapes and formwork production is prohibitively expensive), and various unpredictable errors and deviations that often lead to project that are out-of-budget and out-of-schedule.
While 3D Printing has been around for almost five decades and is traditionally limited to printers of small/medium scale, 3D Construction Printing is a recently developed specific application of the same technologies using equipment in much larger dimensions aimed for use in the construction sector. These processes are using construction materials, such as concrete, and are designed to print whole buildings or their parts. This disruptive new approach brings automation at the core of construction. The structure of a house can now be erected in a single day. Safety is far less of a concern as the printer is doing most of the work, and the printer can work 24 hours a day, 7 days a week. Waste is limited to a minimum as with 3D Construction Printing everything is “made to order” with no need to fit standard sized products for the individual construction. The complex shapes that modern software allows us to design can now be directly translated into reality, without fear of errors or misinterpretations. Additional functions can be directly embedded into the shape of the structure itself, reducing the amount of elements necessary. Shapes can also be optimized, to reduce the quantities of material to the minimum necessary. No matter how intricate the shape needs to be or how many copies are produced, the production speed and the price remain constant and easily predictable.
3D Construction Printing is an array of young technologies that are rapidly developing these years. From the first research and trials made 20 years ago, only few attempts to implement the new concept were made in almost two decades. But, in the last 3-4 years we have witnessed an explosion of different companies, universities, research centers, and associations implementing the concept and experimenting with solutions directly related to 3D Construction Printing. We are even seeing the first real life structures and buildings being made with the help of 3D Construction Printing. With the crucial advantages that 3D Construction Printing brings to the table and many more being developed every day, 3D Construction Printing is paving the way for a fast developing new branch in the construction industry that will revolutionize the way we design, build and live in our buildings in the near and far future.
3D Construction Printing is the most innovative answer to many of the challenges the construction industry is facing today. It is a new set of technologies that will revolutionize and shape the development within the industry for years to come. 3D Construction Printing is here to stay.