Seismic Performance of the Treasure of St. Gennaro's Chapel in Naples (Italy): past and present state

The double calotte dome of the Treasure of St. Gennaro's Chapel in the Cathedral of Naples has been analyzed by means of an interdisciplinary approach regarding a detailed structural assessment. Sequential 3D analyses of the structural complex corresponding to subsequent historical construction and repairing stages (six phases in total) have been performed in the static and dynamic range to investigate the origin of the surveyed crack pattern. The reliability of the model was assessed delineating the areas where high tensile stresses concentrated, with peak values close to the strength of masonry, compared to monitored main damages both nowadays and reported in historical documents and treatises. Looking at the outcomes of various numerical phases it is clearly seen that the dome underwent effective consolidation interventions. It is remarked the skill and cleverness of the ancient technicians who designed proper and accurate interventions, leading to reduced tensile stresses today.