Roman concrete (opus caementicium)
Hormigón romano (opus caementicium)
- Date
- c. 200 BCE · confidence medium
- Place
- Rome and Campania, Italy
- Credited to
- Republican Roman builders
- Field
- Matter & energy
What it is
A mix of lime, sand or volcanic pozzolana and rubble that sets into a monolithic mass, poured between formwork or brick facings. Cheap, mouldable and strong, it freed architecture from stonecutting.
Pozzolana from Pozzuoli is the chemical key: its reactive silica forms hydrated calcium silicates.
What it led to
- Vaults and domes of unprecedented span (the Pantheon, the baths)
- Fast, mass construction with unskilled labour
- Harbours, dams and underwater foundations
- Dense urban planning in multi-storey insulae
Built on
Made possible
- True voussoir arch and barrel vaultc. 300 BCE
- Stone arch bridge142 BCE
- Roman public bathsc. 100 BCE
- Hydraulic marine pozzolanic concretec. 50 BCE
- Large-span concrete dome (Pantheon)c. 126 CE
- Timbrel vault (Catalan vault)c. siglos XIII-XIV
- Quicklime in Roman concrete: hot mixing and self-healing2023
- Dome of the Pantheon
- Marine hydraulic concrete
- Roman baths
- Insula (Roman apartment block)