PSI - Issue 78

Ebrahim Aminifar et al. / Procedia Structural Integrity 78 (2026) 1466–1473

1473

5. Conclusions The study presents a comprehensive typological and statistical analysis of single-nave churches in Italy, extracted from the Da.D.O. database, with the aim of supporting future data-driven fragility modeling. Through systematic filtering based on architectural configuration and data completeness, a homogeneous subset of 1,325 single-nave churches was identified and subjected to geometric, material, and chronological analysis. The dominance of the single-nave rectangular typology was confirmed both numerically and geographically, validating its selection as the reference category for in-depth investigation. A chronological assessment revealed clear patterns in material usage and vertical geometric proportions, offering insights into the evolution of ecclesiastical construction practices across centuries. A comparative evaluation of four clustering algorithms was conducted to classify churches based on floor area. Among them, the Gaussian Mixture Model was selected as the most suitable approach due to its capacity to capture overlapping distributions while ensuring meaningful cluster separation and balance. The study hasn't yet included percentile-based probabilistic modeling or nonlinear structural analyses, but it provides a strong basis for these future developments. Future work will build on this classification framework to define input parameters for structural simulations and to derive typology-specific fragility curves using machine learning and analytical methods. While the current work is limited to the single-nave typology to ensure internal homogeneity, the proposed methodology can be extended to other ecclesiastical configurations in future studies. Acknowledgments The present paper has been developed within the national project promoted by the agreement between the Italian consortium ReLUIS and the Department of Civil Protection DPC-ReLUIS 2024-2026 - WP4 “Seismic Hazard Maps and Damage Scenario (MARS-CARTIS )” References Borri, A., Corradi, M., Castori, G., Sisti, R., De Maria, A., 2019. Analysis of the collapse mechanisms of medieval churches struck by the 2016 Umbrian earthquake. International Journal of Architectural Heritage 13, 215 – 228. https://doi.org/10.1080/15583058.2018.1431731 Dabiri, H., Faramarzi, A., Dall’Asta, A., Tondi, E., Micozzi, F., 2022. A machine learning -based analysis for predicting fragility curve parameters of buildings. Journal of Building Engineering 62, 105367. https://doi.org/10.1016/J.JOBE.2022.105367 De Fabrizio, M., Mallardo, V., 2023. Structural Analysis of Masonry Square Vaults in the Italian Region of Apulia. 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