A multi-level approach for the numerical modelling of complex monumental buildings: Seismic assessment of the "Maniace castle" of Syracuse

Monumental buildings are characterized by elements (such as columns, vaults, arches ...) that can suffer significant damage even under moderate earthquakes. Unfortunately, the available modeling approaches require a huge amount of computing resources. The chapter presents a multi-level strategy that is able to overcome these difficulties by a rational adoption of different computational approaches. As a case study, the non-linear seismic assessment of the medieval "Maniace Castle", in Syracuse (Sicily, Italy) is developed, by using different numerical models. First, the linear behavior of the building is studied by means of two 3D Finite Element models. Then, results are used to calibrate a 2D plane Rigid Body and Spring Model (RBSM), specifically formulated for approximating the macroscopic behavior of masonry texture with a small number of degrees of freedom. In order to account for the variability of the material characteristics, parametric non-linear analyses have been performed and compared.