Dynamic-Based Limit Analysis for Seismic Assessment of Free-Standing Walls of San Giovanni Church in Castelseprio UNESCO World Heritage Site

Free-standing archaeological walls, such as those of San Giovanni Church in Castelseprio (a 5th-century Longobard fortified settlement and UNESCO World Heritage Site), are highly vulnerable to seismic forces due to their lack of structural connections. A dynamic-based limit analysis method was applied here to assess these walls, revealing that the acceleration demand for potential macroblock collapse is two to six times lower than the structure's dynamic amplification response to ground motion. This finding suggests that no immediate intervention is necessary for stability. The study combined on-site inspections, modal identification, and response spectrum analysis to calibrate engineering models of the north and apse walls, identifying critical zones prone to detachment. While the construction quality of the apse was poorer than the north wall, both exhibited compact masonry due to high-quality mortar. Future work could refine the method with nonlinear dynamic analyses and more precise uncertainty modeling.

Sbrogiò, L., Tavano, L., Saretta, Y., Caprino, A., Chavarría Arnau, A., Brogiolo, G. P., & Valluzzi, M. R. (2024). Dynamic-Based Limit Analysis for Seismic Assessment of Free-Standing Walls of San Giovanni Church in Castelseprio UNESCO World Heritage Site. Heritage, 7(1), 448–475. https://doi.org/10.3390/heritage7010022