Design, construction and analysis of a concrete shell using clay formwork, augmented reality and sprayed concrete

Concrete shells offer high levels of structural efficiency and durability, particularly where large spans are required, and dead loads dominate. This project responds to a unique brief for large, enclosed spaces beneath soil and grazing livestock. This made a concrete shell a strong option. Before embarking on that, a smaller prototype was designed, built and assessed. Innovations included the exploration of hybrid textile and steel reinforcement, sprayed concrete, and a shaped clay mound as formwork. Augmented reality was used throughout construction to guide the placing of the clay, formwork and the reinforcement. The success of these was evaluated through lab tests on sprayed concrete samples and a digital point cloud geometry scan, which was analysed to assess the structural impacts of geometric imperfections. This combination of extensive design exploration, construction innovation and abundant data collection revealed many lessons learnt.