2017 Design Digital Fabrication KnitCrete Research sustainability Zurich

We have tested the KnitCrete forming system through several prototypes. The small-scale bridge prototype demonstrator was built using a prestressed hybrid knitted-textile and bending-active structure that acted as a waste-free, stay-in-place, self-supporting formwork. The formwork becomes self-supporting by stiffening the textile with a specially formulated cement paste coating. The extremely lightweight textile weighed only approximately 440g, (around 900g together with the bending active glass fibre rods) and carried 15kg of wet cement-paste coating. The computational design and fabrication of the knitted textile formwork included integrated channels for the insertion of the bending-active rods, tensioning ribbons and features for controlling the thicknesses during concrete casting.

Fact Sheet
  • Global dimensions shell: 1.17m x 2.1m x 0.26m
  • Surface area of concrete: ~3 m2
  • Weight concrete: ~200 kg
  • Weight formwork: 440g (knit) + 900g (glass fibre rods)
  • Type of yarn: Aramid fibre 160TEX

Popescu M., Reiter L., Liew A., Van Mele T., Flatt R.J. and Block P. “Building in concrete with a knitted stay-in-place formwork: Prototype of a concrete shell bridge”, Structures, 14: 322-332, 2018

Related publications

Popescu M., Rippmann M., Van Mele T. and Block P. “Automated generation of knit patterns for non-developable surfaces”, Humanizing Digital Reality – Proceedings of the Design Modelling Symposium 2017, K. De Rycke et al. (editors),: 271-284, Springer, Paris, 2017 (September).

Popescu M., Rippmann M., Van Mele T. and Block P. “Complex Concrete casting: Knitting stay-in-place fabric formwork”, Proceedings of the IASS Symposium, Tokyo 2016 (September)


Concept, Design and Engineering
Mariana Popescu, Andrew Liew, Tom Van Mele, Philippe Block
Coating and Concrete
Lex Reiter, Robert J. Flatt
Fabrication and Construction
Mariana Popescu, Lex Reiter, Pieter Bieghs
Photo and Video
Achilleas Xydis, Demetris Shamas, Mariana Popescu, Lex Reiter
Supported by
NCCR Digital Fabrication, Andreas Reusser, Heinz Richner