Based on the outcomes of the first funding period, this project focuses on the further development of the functionally graded concrete (FGC) building system aiming towards a more drastic reduction of natural resource consumption, greenhouse gas (GHG) emissions and waste volume. The strategy is based on the application of recycling and reuse as the core principles of the circular economy, as well as through the extension of digital design and automated fabrication methods.
Currently, the major part of concrete waste from the demolition of buildings is downcycled for use in road construction*. Through the use of recycled aggregates in concrete mixtures a closed recycling loop can be established. To enlarge its application, mixture designs for eco-self-compacting 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 altered Mix-Designs will be addressed by implementing inherent observation and control methods during production.
Extending the principle of a closed-loop 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 in which elements can be recovered after selective dismantling of structures and subsequently be reused elsewhere.
Further, the digital design and fabrication processes will be extended. This comprises an auto- mated production process for weight-optimized components by the implementation of a digital casting technology with simulative and experimental investigations. Moreover, 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 to the holistic quality assessment as well as to the automated production of functionally graded concrete components.
*A. Rosen, “Urban Mining Index: Entwicklung einer Systematik zur quantitativen Bewertung der Kreislaufkonsistenz von Baukonstruktionen in der Neubauplanung,” Dissertation, Stuttgart, 2021.