from a barrel vault to a groined vault
intersecting barrel vaults
Two perpendiculary placed intersecting barrel vaults form a groined vault.
market of Trajanus
The central hall of the market of Trajanus (early 2nd century - Rome) is roofed by a serie of groined vaults. The long central barrel vault is intersected by several perpendiculary placed barrel vaults. This solution is a better solution than one simple barrel vault.
- as a construction: the perpendiculary placed barrel vaults neutralize each others horizontal forces.
- as a spacial result: the hall becomes higher and larger. The perpendiculary placed barrel vaults allow better natural illumination of the hall providing it a much more open character.
![Image](https://www.geogebra.org/resource/Utr5yGHq/SFVk00VbdnVV2SBa/material-Utr5yGHq.png)
![Image](https://www.geogebra.org/resource/WpMtBGaT/VKIPDNfGJe7UHtTz/material-WpMtBGaT.png)
Baths Caracalla
![Baths Caracalla](https://www.geogebra.org/resource/YM8BuGcm/zsLlKbsKumYWrHQb/material-YM8BuGcm.png)
The baths of Caracalla (early 3th century - Rome) had place for thousands of bathing guests. The construction reaches a span of 30 m, using groined vaults.