KnitCandela

John Hill

1. November 2018

Photo: Philippe Block

The Block Research Group (BRG) at ETH Zurich recently erected KnitCandela, a flexibly formed thin concrete shell, at Museo Universitario Arte Contemporáneo (MUAC) in Mexico City after carrying the knitted formwork from Switzerland to Mexico in a few small suitcases.

A collaboration between BRG, Zaha Hadid Architects Computation and Design Group (ZHCODE), and Architecture Extrapolated (R-Ex), KnitCandela was created as part of Zaha Hadid Architects: Design as Second Nature, on display at MUAC until March 2019. The name pays homage to Spanish-Mexican architect and engineer Felix Candela, who pioneered the design and construction of thin-shell concrete structures. In particular, the installation recalls Candela's Los Manantiales restaurant in Xochimilco, Mexico City.

While Candela's complex yet repetitive hyperbolic paraboloid surfaces were built with reusable formworks, KnitCandela used a cable-net and fabric formwork system. This system, per BRG, enables the construction of "freeform concrete surfaces ... without the need for complex moulds." But most amazing is how light the formwork is relative to the concrete shell: 55 kg (121 lbs) of knitted textile formed the double-curved concrete shell weighing more than 5 tons. The team left the inside layer of the formwork exposed, its colorful pattern referencing the sarape shawls that inspired them.

Watch a short video of KnitCandela's design, shipping, and construction: