Functionally Graded Concrete Building System – Design, Optimisation, Digital Production and Reuse

Building on the results of the first funding period (RP 1-1), this project focuses on the further development of the functionally graded concrete (FGC) building system to achieve a more drastic reduction in natural resource consumption, greenhouse gas (GHG) emissions and waste volumes. The strategy is based on the application of recycling and reuse as the core principles of the circular economy, as well as the extension of digital design and automated fabrication methods.

Currently, the majority of concrete waste from building demolition is down-cycled for use in road construction [1]. The use of recycled aggregates in concrete mixtures can establish a closed recycling loop. To extend its application, mixture designs for eco-selfcompacting concrete (ECO-SCC) using recycled aggregates and alternative binders will be investigated for use in functionally graded concrete components. The challenge of maintaining the required characteristics for such modified mix-designs will be addressed by implementing in-process monitoring and control methods.

Extending the closed-loop principle from the material to the component level, the research will focus on segmented and demountable functionally graded concrete slabs. This approach allows for a slab system where elements can be recovered after selective dismantling of structures and subsequently be reused elsewhere.

Digital design and fabrication processes will also be extended. This includes an automated production process for weight-optimised components through the implementation of a digital casting technology with simulative and experimental investigations. In addition, a design tool for the preliminary design and detailed structural analysis of functionally graded concrete slabs will be established. The tool will be complemented by interfaces for holistic quality assessment and to the automated production of functionally graded concrete components.

[1] A. Rosen, “Urban Mining Index: Entwicklung einer Systematik zur quantitativen Bewertung der Kreislaufkonsistenz von Baukonstruktionen in der Neubauplanung,” Dissertation, Stuttgart, 2021.