The paper is divided in three parts. In the first part the history of the domes and their realisation are 7X:hIl
shortly presented: the Pantheon, Hagia Sophia, St. Mary of the Flower in Florence, St. Peter in ]84YvpfW
Rome. 1 ?]J;9p
In the second part the behaviour of Hagia Sophia is analysed through its history, the observation of mE_iS?1
the present damage and mathematical models. The study shows how the dome collapsed several {9:hg9;E*
times in its history. J<-Fua^
The third part shows the collapse of two vaults of the Basilica of St. Francis of Assisi hit by a strong #J3zTG(:@
earthquake on 26 September, 1997. )Jz !U t
The mathematical model and photographic records explain the mechanism of collapse. Finally the z{V8@q/
reinforcements have been achieved using composite materials with aramidic fibers to strengthen the / ~"AG l.
deformed existing vaults.
