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Exploiting the Potential of Digital Fabrication for Sustainable and Economic Concrete Structures

  • J. Mata-FalcónEmail author
  • P. Bischof
  • W. Kaufmann
Conference paper
Part of the RILEM Bookseries book series (RILEM, volume 19)

Abstract

Digital technologies overcome typical constraints of traditional concrete construction processes caused by the high impact of labour costs and bring about many new possibilities to the conceptual design, dimensioning, detailing, and production of concrete structures. While the potential of geometric flexibility is being extensively explored, most digital technologies encounter difficulties in penetrating the market due to lacking compliance with structural integrity requirements. To maximise their impact, it is essential that digital concrete processes (i) integrate reinforcement resisting tensile forces and (ii) address conventional structures with geometric simplicity. This paper discusses the potential of digital concrete fabrication processes to reduce the quantity of reinforcement required in concrete structures. For example, “minimum reinforcement” can be tremendously reduced by (i) tailoring the concrete grade locally to the actual needs and (ii) ensuring small crack spacings and correspondingly reduced crack widths by means of crack initiators. An experimental study shows that the strength reduction in the interfaces between layers from extrusion processes can be quantified with reasonable accuracy, which allows using these weak interfaces as crack initiators. A mechanical model to quantify the corresponding potential for saving “minimum reinforcement” when using 3D printing is presented. It is found that weak interfaces in layer joints with 33% of the concrete tensile strength inside the layer allow reducing up to 80% the minimum reinforcement for a given maximum crack width requirement under imposed deformations.

Keywords

Digital fabrication Concrete structures Minimum reinforcement Sustainability Durability 3D printing 

Notes

Acknowledgements

This research is supported by the National Centre for Competence in Research in Digital Fabrication in Architecture, funded by the Swiss National Science Foundation (project number 51NF40_141853).

The authors would like to thank Lex Reiter (IFB, ETH Zürich) for his indispensable support for the planning and the conduction of the presented experiments.

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Copyright information

© RILEM 2019

Authors and Affiliations

  1. 1.Institute of Structural Engineering, Department of Civil, Environmental and Geomatic EngineeringETH ZurichZurichSwitzerland

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