Seismic assessment of masonry bell towers by nonlinear analysis and modelling

The assessment and evaluation of historical masonry structures represent a well-known problem in the field of seismic engineering. Indeed, their unique value, often associated with a lack of documentation, represents also a constraint in the testing and evaluation of their geometrical and mechanical characteristics. Among them, bell towers represent a compelling category with inherent complexity, due to their slenderness and to the presence of elements such as large opening and adjacent buildings. In this context, appropriate models to simulate structural behavior play a fundamental role, especially in the definition of proper materials characteristics. The complexity in the behavior of these structures is often related to nonlinearity in material and geometric irregularity, requiring advanced computational tools. Nevertheless, implementing Finite Element Model (FEM), which proves effective in the case of simplified linear models, and performing nonlinear analyses involving the whole structure requires significant computational time, making obtaining reliable results in reasonable time difficult. The aim of this thesis is to explore more efficient modelling strategies. Following this approach, only the most vulnerable part of the structure is simulated with nonlinear laws, while the remaining part will follow a common linear elastic model. The proposed strategy is evaluated on a valuable case study, given by the masonry bell tower of the old parish church of S. Antonio Abate in Montà (CN, Italy), assessing its effectiveness.