UAF Braga, Portugal

Public art should delight but it can also inform and educate. The Urban Algae Folly (UAF) now installed in the central plaza of Braga, north western Portugal is an example of how research into free sources of air cleansing and efficient solar shading is also manifest as a striking art form.

The fern-like form is made up of a great many thin, folded steel plates which have been assembled in a triangulated pattern, some spaces within which are left empty to hold ETFE (Ethylene tetrafluoroethylene) water filled cushions. The water is home to living micro-algae cultures, in this instance Spirulina, which oxygenate the air and very efficiently absorb carbon dioxide. On a sunny day the algae grow quickly and provide effective local natural shading.

Working within a single Rhino model authored by Architects and artists EcoLogic Studio of London, Format Engineers were able to quickly assess the structural geometry within Grasshopper/Karamba by exploiting the shell analysis components. The perforated plates have a solid border and internal Voronoi-derived CNC-cut pattern to minimise mass for assembly, allow light permeation and provide visual interest. The Format team were able to optimise for border-width and plate thickness within a dynamic model that included wind-loading variation driven by changes in plate porosity.

The use of Karamba allowed for rapid virtual prototyping, concept investigation and final analysis (checking against another commercial package revealed insignificant variation). It allowed quick structural feedback on proposed architectural options and thus enabled a contraction of the design process, without which the three-week project delivery programme would have not been achievable.

The Folly was installed on time and has seen a positive reaction from the Portuguese national press.

Find more photos of this project on our website at: http://formatengineers.com/UAF-Braga

Photo: EcoLogic Studio

Format team: Will Pearson, James Solly, Tom Foley, Stephen Melville