Issue 60

F. Greco et alii, Frattura ed Integrità Strutturale, 60 (2022) 464-487; DOI: 10.3221/IGF-ESIS.60.32

Figure 13: Schematic representation of pre-assigned failure mechanisms. A, B, E, F: façade overturning mechanism; C, D, H: apse overturning mechanism; G: belfry overturning mechanism.

Figure 14: 3D representation of the bell tower pre-assigned failure mechanism.

C OMPARATIVE ASSESSMENT AND STRUCTURAL SAFETY PREDICTION s is well known, ancient buildings can usually bear only partially the entity of seismic accelerations provided by the present technical codes. Indeed, various retrofitting systems can be designed with the aim of improving the seismic response of such structures until that all the design seismic actions can be carried by the structural members. To better understand this aspect, the Italian standards introduce the notion of seismic vulnerability indicator, computed as the A

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