The 9th Concrete Design Competition for European students of architecture, engineering and design was hit by COVID-19 just like so many other activities and events over the last year and a half. While originally planned to culminate in Dublin in August 2020 with our characteristic award for national laureates - a weeklong, hands-on international master class working with and exploring the properties of concrete – we had to postpone. Unfortunately, by August 2021 the international situation still had not improved enough to allow us to host an in-person event for 25+ people from all over Europe. We therefore looked at other ways to deliver the international concrete master class. We embraced the idea of a fully digital (distant) practice in which both design processes and fabrication methods would be tested and explored - all within the original timespan of five consecutive days.

The competition theme of FORM-WORKS presented an excellent framework to research relations between digital design processes ranging from experimenting with online design and critic sessions to various digital fabrication techniques to develop the formwork for concrete objects.

The online design sessions, tutoring, critics, and lectures worked efficiently, not least due to the well-trained participants who had experienced similar circumstances for over a year in their respective universities. Being literate in many different online discussion, presentation, and collaboration platforms, from WhatsApp, Zoom, Discord as well as Miro and Google Drive, we were able to cater to all specific needs. 

On the other end of the program, we assembled a small team to receive the design input from the participants, in a variety of software programs and file types, to be developed into manufacturing code for three different fabrication techniques. We offered 3D-printing in PLA, CnC FoamCutting and CnC Milling in foam to produce formwork or inserts for formwork. The participants were organized in five teams of three or four students to ensure that students from different countries had the opportunity to work together.  Each team were given the opportunity to test all three fabrication techniques.

The assignment for the students was as open as possible with the only restrictions on maximum sizes and volume of concrete, all due to production limitations. We planned to produce seven objects per team over the five days. This setup made it possible for teams to try most fabrication techniques at least twice, thus presenting them with an opportunity to not only experience the limitations of fabricating the formwork and the concrete objects, but to also develop a second iteration taking in account the learnings from the first. 

The main challenges for the participants were not the online digital setting of the master class, nor the limiting restrictions of the assignment; far more challenging were the limitations of the digital fabrication methods as well as the physical limitations of working with concrete in objects with such small dimensions.

3D printing in PLA for example results in a very rigid formwork that is hard to demould when complicated or especially delicate shapes are intended. CnC foam cutting is a process in which a straight hotwire is directed though a piece of foam with a 4-axes freedom (two axes on one side, two on the other) that offers some very specific form possibilities and that at the same time presents the designers with very unusual restrictions. Similarly, CnC milling has its own restrictions; the main one being the depth of the cutting bits.  Beside all these machine features another important restriction was the fabrication time per technique, we had to stay aware of our ambition to produce 35 objects in five days; from design to demoulding.

Lastly, the concrete itself offered major learning opportunities. Although we used a high-performance concrete without coarse aggregates, the formal limitations were exceeded more than once. Designing too slender or too complex geometries, combined with rigid formwork and short setting times led to many issues and breaks during the pouring – such as concrete not reaching all the formwork - as well as the demoulding process. Nevertheless, we were able to obtain an impressive ‘grid’ of prototypes - a true overview of the potential of concrete, of formwork techniques, and of this collaborative digital working environment.

The virtual master class proved to be an intense, energetic and exiting experience. Participants were asked to deliver design decisions and results at an unforgiving pace, while collaborating with colleagues they never had met before, with a variety of skills and interests. They did extremely well. In terms of complexity of objects, investigating the potential of the fabrication techniques, the proposals far surpassed our expectations. This presented the fabrication team with their own unexpected challenges. The intended iterations of tests and prototypes reached a maturity, complexity, and refinement we have never seen before in our hands-on master classes. A sign that this virtual program led to more focus and commitment to the design program than before.

Of course, we did miss the in-person contacts that have characterized the Concrete Design master classes thus far. The international exchange of ideas and experiences, the talks, the collaborative spirit and not least the actual physical process of working with the materials.

Fortunately, we did at last get the opportunity to meet up in Dublin during the last week of October. With COVID-19 restrictions more relaxed than in August, it was possible to come together for a weekend in which the objects and formworks produced from afar could be seen, touched, and examined in detail on textures, colour, and form. And we managed to talk directly and celebrate the winning of the competition at last!