Form finding research: development between empirical and numerical methods

The object of form-finding research techniques is to obtain the most efficient shape for static tasks. In civil engineering work, it is applied mainly to bridges and large roofs, the most important structural themes. This research had a strong development in the middle of last century, for the work of both architects and engineers. At the beginning, projects were inspired by natural shapes, like bones, shells and spider nets. The research about tensile structures, like those of Frei Otto, increased the knowledge of the design of shape for various load conditions. Many techniques, like soap films and numerical models, were derived from mathematical research on minimal structures. In Italy, Sergio Musmeci studied the form-finding technique as applied to compressed shell, using method developed for tensile structures: the only difference is the sign of the stresses. But the best spatial shape to transmit them must be the same. He used, at the beginning, empirical models. Later in the '70s, the improved computer power, allowed for the use of numerical methods