Modeling strategies for monumental structures considering history-related phenomena and material uncertainty

The structural diagnosis of existing masonry constructions, which is a fundamental step in the broader framework of the built CH preservation, implies their adequate understanding and modeling. However, this poses several challenges ranging from reproducing complex geometries, dealing with uncertainties on material properties and only partially known building sequences, historical alterations, man-made and natural past damaging events, as well as, in general, a wide range of history-related phenomena that might have left traces on the construction. Therefore, to obtain an adequate comprehension of the assets’ current situation, historical and architectural-stylistic aspects, as well as structural issues should be accounted for in an integrated way. This work contributes to improving the interpretation of the current behavior of CH constructions by proposing a general operating method to systematically address the structural diagnosis through the adoption of diverse investigation techniques and modeling strategies in a cross-disciplinary context between structural engineering and architecture. Within this framework, the work advances in the field of NDTs through the proposal of a new way of exploiting PCs for diagnostic aims; and suggests innovative modeling strategies. On the one hand, it promotes the realization of integrated structural-issue-oriented representative models aimed at assisting structural diagnosis. On the other hand, the research showcases the use of probabilistic theories to address the modeling of different-scale structures, from simple masonry panels to an entire historical building, namely the Baptistery of Pisa, while including material uncertainties. In this regard, in place of traditionally deterministic computational models, a probabilistic setting is first employed to evaluate the seismic behavior of a detailed FE model of the Baptistery by including epistemic uncertainties on the mechanical properties of soil and masonry. Then the setting is used to embed uncertainties on masonry mechanical properties within a non-linear FE model of a significant substructure of the Baptistery, thus illustrating an original way to better understand the construction sequence of the historical buildings by taking advantage of UQ.