Structural Fire Risk for Heritage Buildings by the Performance-Based Engineering Format

This paper discusses and presents an example of fire risk analysis for a case study of an existing heritage building: the Duomo of Modena Cathedral, located in Italy. The main issues related to the application of the fire risk analysis to heritage buildings are discussed in detail, and an ad-hoc procedure is proposed to manage them for the case study. In order to assess the performances of the building in probabilistic terms, the fire risk analysis is conducted by the event-tree method, the fire dynamics are analyzed by numerical thermo-fluid dynamics models, while the structural behavior is investigated by advanced nonlinear thermomechanical finite element models. Results are expressed in terms of risk curves related to a fixed return period, which quantify the occurrence probability of different damage levels induced by fire in the wooden roof of the case study building. This kind of result is fully compatible with probabilistic performance-based engineering frameworks commonly accepted for other hazards (i.e., earthquakes).