An Interdisciplinary Approach for the Geometric, Constructive, and Structural Assessment of Historical Masonry Domes with Application to the ‘Badia di Sant’Agata’ in Catania, Sicily

ABSTRACT

Masonry domes have always represented one of the most fascinating and daring architectural structures, with great symbolic relevance. However, their structural behaviour under environmental actions, such as earthquakes, has not yet been thoroughly investigated. This paper defines an interdisciplinary methodological approach, based on advanced digital survey techniques to evaluate constructive, geometrical, and structural aspects of historical domes. The applied procedure comprises the study of archival documents and diagnostic reports, in-situ analyses and advanced three-dimensional surveys, the development of simplified discrete-element-based structural models, and the performing of pushover analyses. The procedure is applied to a case study represented by the dome of the ‘Badia di Sant’Agata’ church in Catania, an earthquake-prone town located in Eastern Sicily. This church was built after the devastating 1693 earthquake and its dome represents one of the most significant examples among hundreds of masonry domes built in Sicily. The historical and constructive investigation showed that the dome was built without supporting formworks, by laying 21 concentric courses of limestone voussoirs on a peculiar springing ring made of mortared rubble stones. The numerical simulations highlighted that this peculiar ring affects the dome’s failure mechanism and limits its displacement capacity and the maximum shear transferred to the substructure.

KEYWORDS:

• 3D survey and modelling techniques
• discrete macro-element model
• historical construction techniques
• masonry domes
• nonlinear static analysis
• self-supporting structures

Acknowledgments

This study has been conducted within the framework of the agreement on the research entitled “The Baroque domes of Catania. Geometrical, architectural and technological analysis”, stipulated in May 2015 between the Department of Civil Engineering and Architecture, University of Catania, and the Faculty of Engineering and Architecture, “Kore” University of Enna.

The authors would like to thank: Giovanni Turco, former church’s rector, Salvatore Arturo Alberti, designer and construction manager, and Salvatore Lizzio, former director of the Department of Civil Protection of Catania, for granting access to the scaffolding during the last restoration works and authorizing the survey activities; Vincenzo Salanitri of the Department of Civil Protection of Catania for providing the technical reports of the diagnostic investigation; Giulia La Ganga Vasta and Flavia Daidone for the partial elaboration of the drawings, supervised and reviewed by M. Liuzzo and G. Margani; and Laura Floriano for the best fit analysis of the dome, performed under the supervision of M. Liuzzo and G. Margani.

Author Contributions

The authorship of the work is divided as follows: sections 1, 2, and 7: F. Cannizzaro, M. Liuzzo, G. Margani, and B. Pantò; sections 3 and 4: G. Margani; section 5: M. Liuzzo; section 6: F. Cannizzaro and B. Pantò. All authors have read and agreed to the published version of the manuscript.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This research was funded by: the Department of Civil Engineering and Architecture of the University of Catania within the project “SIS-RENEW” and “FIBER-HMS: FRCM masonry Interaction: a novel approach for modelling the BEhaviour of Retrofitted Historical Masonry Structures”, both belonging to the “Piano di incentivi per la ricerca di Ateneo 2020-2022”; the Italian Ministry of University and Research (MUR) within the project PRIN2020 #20209F3A37.