Osservare "ad oggetto di impedir il progresso de'mali" di una Cupola e del suo danno

Santa Maria del Fiore dome is a deeply studied monument, whose mechanical behavior can be hardly described by applying the rough approximations at the base of modern science of construction. The technical “tricks” used by Brunelleschi in order to achieve the best structural behavior, are well known and they have assured masonry resistance and homogeneity for centuries, transforming the octagonal dome into a rotational one. Despite these complex and really efficient inventions, a severe crack pattern affected the dome soon after its construction and it strongly increased in time, being object of different interpretation during centuries – starting from Gherardo Silvani (1693), Giovan Battista Nelli (1695), Ximenes (in 1757), up to the last century Scientific Commissions reports (Nervi in 1936, Sanpaolesi in 1975 and Chiarugi in 1988). An accurate analysis of cracks thickness measurements, both considering the historical data and the last ones recorded by the modern monitoring systems installed on the dome in the last century, has allowed to reliably clarify the origin of this damage. Moreover, it has helped in setting up a reliable and conceivable conservation strategy for this great dome.