ABSTRACT
The idea of the line of thrust appeared in the first half of the 19th century and it was promptly applied to the analysis of domes. Two main approaches were used. On the one hand, the one proposed by Poleni in 1748 for the analysis of St Peter’s dome in Rome, considering the dome divided in separated arches, with a two-dimensional behaviour. However, a dome is a spatial structure, and can develop hoop forces. The matter was addressed in an analytical way but also graphical methods were elaborated since the middle of the 19th century. H.T. Eddy, in 1878, applied a graphical method to masonry domes, considering the absence of tensile strength, and obtaining the point where hoop compression changed to tension. In similar ways, different authors struggled with the same problem. This paper summarizes the different approaches, together with application to real cases.
