Commissioni ministeriali e prime indagini strumentali sulla Cupola del Brunelleschi: l'inizio di un processo

The mechanical analysis of Santa Maria del Fiore dome is a complex issue, which can be hardly described by apply-ing the rough approximations at the base of modern science of construction. Despite the wellknown technical “tricks” arranged by Brunelleschi in order to achieve the best structural behaviour, the dome is affected by a severe damage which started soon after its construction and strongly increased in time. This complex crack pattern has been object of different interpretation during centuries, starting from Silvani (1693), Nelli (1695), and Ximenes (in 1757). But it was only in the XXth century that the dome was transformed into a sort of "restoration laboratory", precisely by the institution of several Ministerial Commissions (Nervi-Sanpaolesi in 1936, Sanpaolesi-Di Pasquale in 1975 and Chiarugi in 1988). This paper aims to describe the different methodologies suggested and applied by these Scientific Commissions with the final aim to reconstruct the process of investigation made on this impressive dome, which represents not only an architectural masterpiece but also a great “site of knowledge”.