Structural strengthening of the masonry dome of the Cathedral of St. Michael the Archangel in Cariati (CS)

The field of cultural heritage has as its main objective the conservation of the historical evidence "through a coherent, coordinated and planned activities of study, prevention, maintenance and restoration" [1]. The interventions aimed at defend the historical material, however, are often designed and executed only when situations of damage, mostly irreversible, are in act; this put at risk the generic cultural asset which records its partial or total loss. As known, the world of cultural heritage is today the "emergency system" for excellence, to cause of structural problems related mainly to the lack of economic means. In such a context there isn't the implementation of the most important conservation measure, namely the prevention, understood as "the system of suitable activities to limit the situations of risk linked to cultural heritage in its context" . In this paper, a diagnostic plan aimed at evaluating the seismic safety of the masonry dome of the Cathedral of St. Michael the Archangel in Cariati (Cs) has been performed. In order to suggest a action of prevention suitable to limit the seismic risk of this architectural element, a strengthening system of the dome has been designed, which involves the use of tissues in composite material reinforced with glass fibers GFRP, able to guarantee an effective structural improvement. A static analysis performed on the domed element according to the membrane theory, as well as the design of the strengthening intervention have been preceded by the territorial, historical and architectural contextualization of the cathedral.