Besides the big conglomerations a satellite is only able to see the Chinese Wall as single building – in this sense the structure of the PVC membrane shading system in Milano competes with a thousands of years old structure on the other side of the world. Mehler Texnologies provided the material for the huge sun shading systems of the Expo 2015 paths.
In ancient Rome, the main street that crossed the village from East to West was called “Decumano” and the perpendicular street from North to South was called “Cardo”. These are also the names of the two main walkways of the Expo exhibition area. As Milan gets quite hot during summer the designers of the Expo area decided to cover the two axes in a way that the old Romans would certainly have appreciated as well: it seems that the fabrics are only loosely fitted to the grid system. Taiyo Europe was chosen to cover these two streets which together are around 1.700m long with a covered surface close to 70.000m². This structure represents one of the biggest PVC roofs in Europe. Moreover the street called “Percorso Secondario”, which connects the Decumano and the West access was covered. This is a structure made of ETFE cushions for a total surface of 2.000m². The Decumano is composed by a modulus of around 50m that is reproduced 30 times, one after another, interrupted only one time at the intersection with the Cardo, which is also composed by such modulus. The Secondario structure is a 200m long strip. At the end of it we can find the West access that has a dimension of around 100m x 20m. Project overview The structure is composed by more than 400 steel columns of 17m height; supporting and stabilizing cables are connected to the columns and more than 2000 steel beams were installed between the cables in order to support the membrane. Taiyo Europe’s scope of work was on the one hand, to install the steel provided by the client and on the other hand to install more than 300 PVC panels of Mehler fabric, some of them processed in Europe and some in the sister company in Australia; one of the biggest challenges was to coordinate the work without blocking the other companies that were working on the pavilions area. The Decumano was, in fact, the only access to the working areas of all the country pavilion, so during the most busy phase, more than 9.000 people were working on the entire Expo jobsite. The membrane used to cover the Decumano, Cardo and Percorso Secondario is a special PVC material with two different colors: white on the top and beige on the bottom. This came from a study of the “Politecnico di Milano” that investigated how to create a good microclimate under the membranes in order to assure the best comfort for the visitors. The asymmetrical shape of the structure has this objective, in fact the “up and down” structures of the membranes not only allow the air to circulate but also helps avoiding the “tunnel effect”. It is good to see tensile structures in a way that seems natural – indeed a straightforward approach to this ephemeral structure. Here it is easy to imagine that there will be a second life for these fabrics after the Expo closes its gates. If the Expo organization doesn’t leave the Decumano on site for future uses, Taiyo Europe, and Mehler Texnologies have ideas at hand to recycle the membrane as shelters for refugees. As the structures at the Expo follow a rather simple cutting pattern, it would be easy to recycle the material for tents.