Corbelling (the false arch and false dome)

Assembled from 24 blocks · 1 evidence · 31 related

1. Story
2. Spanning an opening by stepping successive courses of masonry inwards until they meet, then usually trimming the profile smooth. Each course is held down by the weight of the wall behind it, so the stones are cantilevers, not voussoirs: nothing is wedged, and the structure works by bending and self-weight rather than by pure compression along a curve. Corbelling is the older technique and it is spectacular within its limits - the Grand Gallery of the Great Pyramid and the Mycenaean tholos tombs are both corbelled - but it needs an enormous mass of masonry above and behind the opening, so it becomes uneconomic quickly as the span grows. A corbelled profile looks like an arch and is not one, and the distinction is the single most useful thing a visitor can learn to see.
3. Knowledge
4. Corbelling (the false arch and false dome)
5. The voussoir arch
6. Connections
7. Great Pyramid of Giza (Pyramid of Khufu)
8. The voussoir arch
9. The voussoir arch
10. Treasury of Atreus, Mycenae
11. The Great Pyramid is built as mass, not span
12. The corbelled tholos at Mycenae sets a record that stands for fourteen centuries
13. Colosseum (Flavian Amphitheatre), Rome
14. Pont du Gard
15. Load path
16. Corbelling (the false arch and false dome)
17. Corbelling (the false arch and false dome)
18. The dome
19. The Gothic rib vault
20. Roman builders adopt pozzolanic concrete
21. The Pont du Gard carries an aqueduct on three tiers of arches
22. The Colosseum opens: arch and concrete at civic scale
23. Evidence
24. 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.