Issue 51

C. Anselmi et alii, Frattura ed Integrità Strutturale, 51 (2020) 486-503; DOI: 10.3221/IGF-ESIS.51.37 496 Features Compared cases Increase % Decrease % (a) 1-5 68.637 (a) 2-7 77.73 (a) 3-9 45.570 (a) 4-11 55.188 (b) 5-6 34.940 (b) 7-8 140.693 (b) 9-10 7.012 (b) 11-12 9.936 (c) 1-2 41.049 (c) 3-4 10.074 (c) 5-7 58.141 (c) 9-11 25.964 (d) 1-3 34.171 (d) 2-4 104.672 (d) 5-9 132.853 (d) 7-11 311.843 Table 2 : Compared cases. no failure at ribs 0 2 4 6 8 10 12 14 16 0 200 400 600 800 1000 1200 1400 alpha Nh Diagram alpha vs Nh (Lf=2m) failure at ribs alpha vs Nh 0 5 10 15 20 25 30 0 0,5 1 1,5 2 2,5 alpha Lf Diagram alpha vs Lf (sT=1,5m) failure at ribs no failure at ribs 0 5 10 15 20 25 30 35 1,5 2 2,5 3 3,5 alpha sT Diagram alpha vs sT (Lf=2m) failure at ribs no failure at ribs Figure 12 : Variability of α  multiplier as a function of Nh, Lf and sT. Fig. 12 shows the variability of α multiplier as a function of Nh, Lf and sT parameters. Furthermore, some compared cases of Tab. 2 are shown in the following subparagraph 7.1 together with the relative collapse mechanisms. Finally, in subparagraph 7.2, some results obtained by examining the most famous pavilion dome in the world, that of S. Maria del Fiore by Brunelleschi in Florence, are illustrated. Some compared cases with relative collapse mechanisms We refer to compared cases shown in bold in Tab. 2. Only for practical display reasons the comparisons relating to the four features listed above with (a), (b), (c) and (d) will be illustrated below in order (c), (a), (b) and (d). As previously mentioned, Figs. 13-17 show the collapse mechanism of a quarter of a dome, represented through axonometric and zenithal views, and a section.