The paper is divided in three parts. In the first part the history of the domes and their realisation are 7I
X Wv-
shortly presented: the Pantheon, Hagia Sophia, St. Mary of the Flower in Florence, St. Peter in j2<+[h-
Rome. $Gv@lZ@=
In the second part the behaviour of Hagia Sophia is analysed through its history, the observation of t]@>kAA>2L
the present damage and mathematical models. The study shows how the dome collapsed several >kK@tJn
times in its history. j<*7p:L7_>
The third part shows the collapse of two vaults of the Basilica of St. Francis of Assisi hit by a strong l|?tqCT ^h
earthquake on 26 September, 1997. _&B K4?H@b
The mathematical model and photographic records explain the mechanism of collapse. Finally the YHQ]]#'
reinforcements have been achieved using composite materials with aramidic fibers to strengthen the suwR`2
deformed existing vaults.
