Author
A. ANZANI AND L. BINDA,
Politecnico di Milano,
G. MELCHIORRI
ENEL CRIS, Milano

Abstract
After the collapse of the Civic Tower of Pavia in 1989 and of a bell Tower in Goch in 1995 concern about the stability of non-homogeneous massive masonry structures encouraged the study of long term behaviour of rubble masonry materials under persistent loads. Clear time dependent behaviour has been found during the experimental work carried out on the materials of the collapsed tower of Pavia, the results of which are presented here. This aspect seems to be particularly important when the structural safety of historical buildings has to be evaluated. In addition, its combination with the action of cyclic loads can increase the material damage leading to dangerous situations.