Author: Edward Wakefield
“Concrete, as you probably know, is not a very environmentally-friendly material. It comes with a lot of carbon emissions. So that’s a big issue. What our project is trying to do is to marry these two ideas. One is construction 3D printing, which I would say is a more environmentally-friendly construction process for two reasons – you do not need to place concrete anywhere else but at the locations where you need it, and you don’t need formwork, which you would usually use just a few times and then throw it away. So these are two major benefits of the process itself. Now we try to marry this process with a sustainable material. That sustainable material is hempcrete. Hemp by itself is a very attractive material to us in construction because it, essentially, has a negative carbon footprint – it sequesters a lot of CO2. What we’re trying to do in this project is print using hempcrete. That’s the big challenge.”
The team will also be looking at the structures’ performance over time. If a structure itself is sustainable, at face value, but needs to be replaced or repaired every few years due to hurricane damage, for example, then it is not truly sustainable. To prove the hypothesis, the team will have to find the harmonious balance between sustainability and resilience – and study how the two affect each other.
In terms of the process of turning the hemp plant into hempcrete, Petros Sideris noted that he is not a materials engineer, and he may not be the best person to explain the process to us, “But what I can tell you is that we’re looking at different parts of the plant. We’re looking at using hemp fibers, and we’re also looking at some more innovative approaches, such as hemp powder, for example. We’re looking at how we can use those materials to get a mix design that would be printable and at the same time environmentally friendly.”
Concerning modifying the hempcrete to be 3D printable – “We have a plan on how to do that. We have thought about different ideas, and we have some specific ideas on how to do it. What we’ve been doing so far, even prior to the formal initiation of this project, is that we have already started talking to producers and seeing what materials we have available, and discussing what we expect we would need. We have also had some preliminary work in those directions. We believe that our approach will address the challenge of having a 3D printable hempcrete mix design.”
This is one of many such stories I have found that were all published very recently, indicating a lot of current activity in the scientific community exploring new materials, especially sustainable ones, to combine with the efficiency of large-scale 3D-printing. For one, this provides a great deal of hope that 3D printing construction will not only reduce concrete usage, but also be able to make use of entirely new sustainable construction materials.