Material-Constructive Features and Structural Behavior of Sicilian Thin Shell Vaults

Thin-tile vaults, characterized by a wide variety of geometric configurations, represent an important part of the architectural heritage in Southern Italy. Many of these structures are still in serviceable condition. However, the absence of dedicated design guidelines and the need to comply with modern safety and serviceability requirements make their assessment and conservation a challenging task. The present study contributes to a more informed and responsible approach to these historic systems by addressing current normative limitations and by clarifying the structural role of construction elements such as counter-vaults and stiffening ribs. The research focuses on a representative case study located in Sicily, where this technique was extensively used from the late eighteenth century. The investigation combines direct on-site surveys, laboratory characterization of collected material samples, and numerical analysis based on finite-element elastic modeling. The results show that the traditional building knowledge, commonly described as the art of good manufacturing and transmitted through long-standing craftsmanship, produced a construction technique that still fulfills its structural function with remarkable effectiveness.