Arena Fonte Nova, Brazil: low prestress for a lightweight roof

The new Arena Fonte Nova in Salvador de Bahia, Brazil off ers an innovative lightweight solution for a large-span roof. The spoke-wheel system is enhanced by drawing on stiff ness and load-bearing capacity from bracings in the vertical plane of the tension rings and in the horizontal plane of the compression ring. This allows prestressing to be reduced to 50% of the usual level. Other important features that simplify the design and reduce costs are concave radial cables with compression elements, using fewer arches with non-uniform membrane prestress, and a fl at overall roof slope. The low prestress brings cost savings both by reducing the weight of all primary structural elements and also by incurring smaller forces during installation.