The dome

Assembled from 26 blocks · 2 evidence · 31 related

1. Story
2. An arch rotated about its vertical axis, and therefore a surface rather than a line. The rotation changes the behaviour in one important way: alongside the compression running down the meridians, the horizontal rings of the shell (the hoop direction) carry force too - compressive near the crown, tensile lower down. That hoop tension is why masonry domes crack radially near their base almost as a rule, and why builders girdle them with iron chains, thicken them into a drum, bury them in stepped rings of masonry, or accept the cracks and watch them. A dome also concentrates its outward thrust onto whatever it sits on, so the real design problem is rarely the shell and almost always the supports. Domes were built long before anyone could calculate any of this; the mathematics of shell behaviour arrives in the 18th century and after, many centuries later than the buildings.
3. Knowledge
4. The voussoir arch
5. The dome
6. Connections
7. The voussoir arch
8. The pendentive
9. The Pantheon, Rome
10. The Pantheon dome spans about 43 m in unreinforced concrete
11. Hagia Sophia is dedicated
12. The first dome of Hagia Sophia collapses
13. The steeper dome is dedicated
14. Colosseum (Flavian Amphitheatre), Rome
15. Pont du Gard
16. Load path
17. Corbelling (the false arch and false dome)
18. Corbelling (the false arch and false dome)
19. The dome
20. The Gothic rib vault
21. Roman builders adopt pozzolanic concrete
22. The Pont du Gard carries an aqueduct on three tiers of arches
23. The Colosseum opens: arch and concrete at civic scale
24. Evidence
25. Comparative structural analysis of large pre-industrial buildings, treating span, thrust and material strength as the variables that determine what each period could build. Supports the load-path framing used throughout this pack and the structural contrasts drawn between post-and-lintel, corbelling, the voussoir arch, the dome and the rib vault. V55 verification basis: this volume is a real and standard reference named in the Journey declaration, but it was NOT consulted in this session - WebFetch is refused by the environment egress proxy for all research domains and the session WebSearch budget was exhausted before production began.
26. Standard study of Roman concrete vaulting, its materials, aggregate selection and construction sequence, including the graded-aggregate practice used in large domes. Supports the MATERIAL_ROMAN_CONCRETE and SITE_PANTHEON records. V55 verification basis: real and standard, but not consulted in this session; no research domain was reachable.