I Tufi vulcanici nel costruito storico: vulnerabilità e possibili trattamenti per la conservazione e il restauro

Goal of this research is to deepen the knowledge about some lithotypes belonging to two important volcaniclastic formations: The yellow and grey Campanian Ignimbrite and the Neapolitan Yellow Tuff. These materials, widely used in the historic architecture of Campania, represent a fundamental element of the cultural heritage, whose protection and preservation cannot disgregard a deep knowledge of the lithotype itself, as well as the context it is used in as building material. For this purpose, the main uses of these volcaniclastic formations as building material and as ornamental stones along with their distribution in the areas of main historic interest was investigated. The main features of these materials were evaluated from a mineralogical and chemical point of view. Furthermore, due to lack of information so far available, a deep investigation was carried out from a petrophysical point of view. A careful investigation allowed to evaluate the decay phenomena occurring in these materials due to interaction of the stone with the weathering agents such as humidity and temperature. At the some time, physical and chemical processes were also studied as a consequence of the decay phenomena, following the modifications occurring in the stone after ageing tests. It was finally verified the experimental use of consolidant and protection agents aimed at improving the compactness and strength resistance of the rock, by modifying the inner texture and wheneven possible, limiting water infiltration.