Fragility models for the large-scale seismic vulnerability assessment of masonry buildings

The frequent earthquakes and the high vulnerability of existing buildings, especially unreinforced masonry structures, have historically led to severe physical and socio-economic impacts in countries like Italy. This underscores the need for detailed risk assessments to support large-scale evaluations and inform effective mitigation strategies. In this context, this dissertation aims to assess the fragility of masonry structures through a comprehensive approach that combines empirical data, analytical modelling, and scenario simulation techniques. The research begins with a comprehensive overview of the main current challenges and uncertainties that seismic fragility assessment methodologies are facing and then delves into three key parts of investigation following different approaches. Firstly, an empirical fragility model is developed, derived through a detailed analysis of observed damage data from the 2012 Emilia earthquake. Subsequently, a simplified analytical methodology is introduced to generate typological fragility curves, enabling efficient large-scale vulnerability assessment of the building stock. Finally, damage scenario simulations are conducted to rigorously test and compare various fragility models under real seismic conditions, evaluating their predictive reliability and practical application. Through this multi-perspective approach, the research contributes to an advancement of the methodologies for assessing seismic vulnerability and risk, highlighting the importance of integrating observed data and simulated scenarios to enhance the accuracy of seismic assessments. The findings highlight the critical need for further refinement of existing models to enhance risk predictions, allowing to plan mitigation actions able to increase the resilience of the building stock to future seismic events.