Inauguration of the world’s biggest convertible in Frankfurt

This multifunctional arena, costing 188 million euros and replacing the former “Waldstadion” of Frankfurt, offers seats for 48,500 people. During First Division games even 52,000 people can enjoy the games, as seats can be transformed into standing room. With its promotion into the German First Division, the football club ”Eintracht Frankfurt” is now top-class– just as the new stadium. The roof of this modern stadium truly deserves our attention. It consists of a membrane whose middle part can be fold and unfold within minutes above the playing field. If it is fold, it disappears as a video cube above the kick-off area. Hence it is called « the world’s biggest convertible ». The actual load-bearing structure of the roof made of steel and ropes lies under this membrane protecting against wind and rain: it reminds us of a lying spoke wheel, standing on supporting pillars above the top rim of the stand. The inner hub is composed of a 20 t- welded steel construction and the spokes are made of ropes. The outer rim consists of an elliptical ring. This 709 m long ring was welded together of steel heavy plates with a box-like cross section of 1.00 x 1.50 m. For this ring construction, the heavy fabrication department of Dillinger Hütte delivered 1,000 t of heavy plates in a thickness range of up to 65 mm, which were welded together to 44 16-m-long boxes and assembled on site. One year ahead of the World Cup, the high-quality steel heavy plates of Dillinger Hütte turn out to be sporty : other modernised or newly constructed stadiums used heavy plates from Dillingen. For the recently opened Allianz Arena in Munich with its modern and futuristic design 2,000 t of heavy plates were delivered. The load-bearing constructions of the multifunctional arena in Dusseldorf as well as of the new Olympic stadium in Athens have a heart made of steel from Dillingen.