The paper is divided in three parts. In the first part the history of the domes and their realisation are xGd60"w2
shortly presented: the Pantheon, Hagia Sophia, St. Mary of the Flower in Florence, St. Peter in S=@+qcI
Rome. iJs~NLCgVu
In the second part the behaviour of Hagia Sophia is analysed through its history, the observation of w~ 3X
m{
the present damage and mathematical models. The study shows how the dome collapsed several '.A!IGsj
times in its history. il0K ^i
The third part shows the collapse of two vaults of the Basilica of St. Francis of Assisi hit by a strong =ZgueUz,
earthquake on 26 September, 1997. O. * 0;5
The mathematical model and photographic records explain the mechanism of collapse. Finally the iE%" Q? Q/
reinforcements have been achieved using composite materials with aramidic fibers to strengthen the !cW rB9
deformed existing vaults.
