Structural Investigation of 18th-Century Ogival Masonry Domes: From Carlo Fontana to Bernardo Vittone

In this study a structural investigation on the ogival masonry domes is performed with particular attention to the significant debate between mathematicians and architects mainly of the French and Italian schools that characterized the 18th century. In this period, analytical approaches to investigate the static of dome structures were developed concurrently for the affirmation of the proportional methods, as reported in several architectural treatises in which graphical constructions for the design of masonry domes can be found. It is well known that Carlo Fontana, in 1694, was the first to show in detail the geometrical rules for the design of a masonry dome. Later, in 1760, the Italian architect Bernardo Antonio Vittone proposed some variations to the rules written by Fontana in order to increase the height of the dome and the slope of the meridian section at the intersection with the lantern. In this study, Vittone’s dome has been analyzed and compared with Fontana’s dome by means of an analytical approach that also considers the influence of the lantern at the top. The obtained results confirm that Vittone’s rules lead not only to architectural, but also structural improvements.