On-site investigation on the remains of the Cathedral of Noto

摘要

The Cathedral of Noto was damaged after the earthquake that hit Sicily in 1990. Soon after the event, cracks appeared on the domes of the lateral naves, and also on the pillars. In 1992 some provisional work had been carried out in view of confining the pillars of the central nave that were damaged. Some pictures made after the earthquake also show clearly the presence of moisture rise on the pillars and walls. A sudden collapse due to the damages was probably not expected, so that no other measures were taken to better strengthen and repair the structures. Only after the collapse of the Civic Tower in Pavia (1989) and the following research (Masonry Int J 6 (1992) 11, Second International Conference RILEM on Rehabilitation of Structures, Highett, Australia (1998) 542), it was clearly shown that in case of high stresses on low-strength masonry an existing damage can slowly lead to partial or total collapse of the structure over a long time. It seems a confirmation of this long-term behaviour of the structures that the Cathedral collapse took place in 1996, 6 years after the earthquake, which had certainly caused high damages to the structure.