Francesco Di Paola, Pietro Pedone
This study is part of a more extensive research that aims to examine in depth the geometrical-spatial origin of skew curves belonging to conical surfaces of revolution: conical spiral and conical helix. The study begins with an investigation concerning the geometrical tracing, and the spatial origin of both the skew curves and the ruled surfaces they generate, carrying out a comparison of the different formal characteristics through a number of algorithms that control the reference properties, written within the renown Rhinoceros plug-in, Grasshopper. Then follows an in-depth analysis of an admirable example of architecture dating back to the first thirty years of the past century and made by the Architect Engineer Giuseppe Momo: the double-ramp helicoidal stair, located at the entrance of the Vatican Museums in Rome (1929-1932). According to project designs found in literature, and through innovative graphical analyses, the geometrical-formal system of the work object of study is here illustrated.
The study deepens the geometric-spatial genesis of a wonderful example of conical helical staircase at the entrance of the Vatican Museums. The Momo architect determines genial technical solutions, ensuring the security and comfort along the staircase and emphasizing at the same time the development of the spiral slab.
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