Evolution of material-efficient concrete girders: Conceptual design informed by topology optimisation and experimental testing regime

Today’s concrete design is characterised by an underutilisation of the used materials. However, an increase of resource-efficiency within structural concrete design is urgently needed. Topology optimisation is, hence, consulted within the present study as a potential approach to design material-efficient concrete girders. In four sequential test series the interrelations between design, material and fabrication were carved out. In particular the presented method made it possible to understand inherent peculiarities in the structural behaviour of optimised, truss-like concrete girders, e.g. a failure mechanism due to deflection forces. The findings also led to the elaboration of a design flow, that was successfully applied to the final test series resulting in significant resource savings while guaranteeing a ductile failure mode. A final performance increase of the material-efficient concrete girders of almost 40% could be achieved, measured by the Global Warming Potential of the used materials’ production phase divided by the experimental maximum load. • Topology-optimised concrete girders are put to test along four development stages. • Mass-reduced concrete girders with novel reinforcement concepts are realised. • A performance increase of the girders of almost 40% could be achieved. • An accurate material characterisation is essential to reach successful results. • A direct relation between a reduction in mass and environmental impact is not given.