KnittETH concrete canoe

KnittETH is the ETH student entry for the 17th Concrete Canoe Regatta held in Heilbron in 2019. The canoe was built using KnitCrete – a CNC knitted textile that served as formwork and was coated with a specifically developed cement paste. Weft-knitted textiles make it possible to integrate features such as channels and openings in a single manufacturing process, without the need for time-consuming patterning and stitching of parts together.  Taking advantage of this possibility to integrate channels into the textile, a thin canoe with stiffening ribs that provide rigidity was designed.

To underline the lightness of the system, compact transport, and ease of construction the canoe was built on-site one day before the race. The custom textile was hung in a timber frame including shaping splines. Concrete was cast in the channel openings and gravity shaped the final geometry of the canoe. Finally, a layer of cement paste coating was applied to the interstitial surfaces to waterproof the canoe surface. Once hardened, the canoe was removed from the frame ready for the race!

KnittETH was awarded the second prize in the category “Construction”