Adapting Smart Dynamic Casting to Thin Folded Geometries

  • Anna SzaboEmail author
  • Lex Reiter
  • Ena Lloret-Fritschi
  • Fabio Gramazio
  • Matthias Kohler
  • Robert J. Flatt
Conference paper
Part of the RILEM Bookseries book series (RILEM, volume 19)


The first thin folded concrete prototypes produced with Smart Dynamic Casting (SDC) exposed numerous challenges concerning concrete. The SDC process is modelled to explain the increased difficulty to fabricate thin folded members compared to columns. Due to the smaller volume to surface ratio in formworks for thin folded structures the effect of friction is amplified and the process window narrows down. In order to compensate for this, retarded self-compacting mortar mix designs and acceleration strategies are investigated.

Material testing results provide guidelines of how to achieve a uniform hardening rate over the course of an experiment, while preserving sufficient fluidity and dealing with variations in raw materials. For this, offline penetrometer tests are performed to evaluate material properties and online measurements are recorded to follow the strength evolution of the same mix processed with the experimental setup. In addition, the slipping criterion and the deformability of the concrete are tested in a 1:1 scale robotic experiment to evaluate the fabrication feasibility with the adapted mix. This unveils the potential to produce thin folded members for architectural applications.


Smart Dynamic Casting Folded structures Process window 



The research is pursued in the interdisciplinary framework of the National Competence Centre of Research (NCCR) Digital Fabrication funded by the SNSF at ETH Zürich.

The authors thank Heinz Richner, Andi Reusser, Michael Lyrenmann for technical assistance, Tom Mundy, Lukas Sigrist, Shaun Wu and Federico Giacomarra for their help during the experiments. The authors are also grateful for the constructive discussions with Nicolas Roussel and Timothy Wangler.


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Copyright information

© RILEM 2019

Authors and Affiliations

  • Anna Szabo
    • 1
    Email author
  • Lex Reiter
    • 2
  • Ena Lloret-Fritschi
    • 1
    • 2
  • Fabio Gramazio
    • 1
  • Matthias Kohler
    • 1
  • Robert J. Flatt
    • 2
  1. 1.Gramazio Kohler Research, NCCR Digital FabricationETH ZurichZurichSwitzerland
  2. 2.Institute for Building Materials, NCCR Digital FabricationETH ZurichZurichSwitzerland

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