Simplified numerical approach for the structural analysis of monumental historical aggregates: the case study of Certosa di Calci

Monumental historical buildings are worldwide recognized as a fundamental component of the World Cultural Heritage to be preserved for future generations. Their structural performance analysis needs to face challenging issues such as the usually limited initial knowledge, the generally large dimensions, and the great structural complexity coming from overlapped construction phases over centuries. The structural behavior of historical constructions, therefore, differs from ordinary buildings, since resulting from the interaction of different parts, recognizable as 'structural units'. A methodology accounting for all the peculiarities of monumental masonry buildings is proposed with reference to the specific case study of La Certosa di Calci (Italy). The monumental cluster is ideally decomposed into its structural units based on a preliminary knowledge phase, allowing to perform detailed structural analyses only on selected areas without resorting to a cumbersome and time demanding global model. The aggregate-effect influence over the structural behavior of a single unit is investigated by means of nonlinear analysis performed on different configurations. Achieved results are accurately analyzed, finally proposing a simplified model where one structural unit is represented through a FEM model and the interaction effects due to the adjacent portions are simulated through a calibrated spring system.