Thomas Juul Andersen is team leader at the Concrete Centre at Danish Technological Institute. He has been working with 3D concrete printing for several years and is leading the N3XTCON research project in which DTU is also participating.
1. Where is 3D concrete printing used?
In Denmark, there are only a few examples of concrete printing on construction sites. In the USA, Russia, China, and Dubai, for example, there are currently a number of examples of printed constructions. However, the trend in these countries is that they just produce traditional concrete structures in a new way. In Europe, we are more concerned with exploring the architectural possibilities of the technology.
2. How can technology improve construction sustainability?
Material selection is key here. In many places, it is not concrete that is used at all, but rather a mortar-like material. Unfortunately, typically it has a bigger carbon footprint than concrete. The development of new concrete solutions with lower cement content, for example, is therefore key to ensuring that 3D concrete printing becomes a climate-friendly solution. This is one of the things we are exploring in the N3XTCON research project.
3D concrete printing has great potential to reduce material consumption in concrete construction. This is because it is an additive solution—i.e. only the material to be used is added. For example, if you want to print a column, you don't have to print a solid column. You might be able to make do with a hollow column.
The technology also provides for the optimization of constructions where you only utilize materials in load-bearing areas of structures. This also helps reduce material consumption and promote sustainable construction.
3. Where will we be in ten years' time?
We may have the printers, but in terms of materials and architecture, we're still not quite there yet. My guess is that we might be in three to five years' time. It may be a further five years before we see 3D concrete printing more widely used in Danish construction. However, in the past, such revolutionary technologies have demonstrated the ability to take unexpected quantum leaps forward, so perhaps things will go much faster.
