Non destructive testing techniques applied to the masonry and timber structures of the Crocifisso Church in Noto

After the partial collapse of the Cathedral of Noto in Sicily, damaged by the 1990 earthquake, which hit the Easthern part of the Italian island, an extensive investigation carried out on site and in laboratory allowed to detect a pre-existing damage of the pillars due to long term behaviour of the material under compressive stresses. The investigation extended to other churches and buildings showed cases of progressive damage, which can in an unknown time, bring the structures to sudden collapse. The paper presents and discusses the preliminary results of the research carried out by the authors on the Crocifisso Church in Noto, built in the same period and with material similar to the ones of the Cathedral. The investigation programme was planned, aimed to evaluate the state of damage of the structure and to design the preservation and restoration actions.