The paper is divided in three parts. In the first part the history of the domes and their realisation are ^GY^g-R
shortly presented: the Pantheon, Hagia Sophia, St. Mary of the Flower in Florence, St. Peter in ov,s] g83
Rome. hB.8\-}QMq
In the second part the behaviour of Hagia Sophia is analysed through its history, the observation of s_fe4K
the present damage and mathematical models. The study shows how the dome collapsed several *#Ia8^z=p
times in its history. ;)CN=J!
The third part shows the collapse of two vaults of the Basilica of St. Francis of Assisi hit by a strong sfn^R+x4,9
earthquake on 26 September, 1997. Er~KX3vF
The mathematical model and photographic records explain the mechanism of collapse. Finally the +ynhN\S$/
reinforcements have been achieved using composite materials with aramidic fibers to strengthen the HB5-B XBU
deformed existing vaults.
