The Leaning Tower of Pisa
ByJ.B. Burland, M. Jamiolkowski, N. Squeglia & C. Viggiani
Pages 22

ABSTRACT: The Leaning Tower of Pisa is one of the world’s best known and most treasured monuments. It was erected in the Middle Ages, at the time of maximum power of Pisa. The Tower is founded on highly compressible soils and started leaning from commencement of its construction. In the 1990s the overhang had reached the value of 4.7 m and was increasing at a rate of 1.5 mm per year; an analysis of the situation showed that a collapse was to be expected within some decades.