The Romans didn’t invent concrete, but they did establish its versatility. The structural ingenuity of the Baths of Caracalla, the Pont du Gard and the Pantheon would not be surpassed for a thousand years.
But if the dazzling concrete curves and cantilevers of modern architecture have matched the Romans’ for style and structure, today’s standard recipe, 2,000 years later, remains in some ways inferior.
New research into Pozzolanic cement, so named for the corner of the Bay of Naples where the ash of Mount Vesuvius facilitated its creation, shows the advantages of the Roman method. Their mixture for hydraulic concrete, a blend of volcanic ash and lime, has a tougher molecular structure than its modern equivalent. It’s unusually resistant to fragmenting and nearly immune to the corrosion caused by salt water. That’s why Roman jetties and port structures have weathered two salty millennia, while our maritime concrete creations degrade within a matter of decades.
So why aren’t we doing as the Romans did?
For one thing, the methods largely vanished with the fall of Rome. They really haven’t been examined at a very fine scale until now,
says Marie Jackson, one of the researchers who has been studying the molecular composition of Roman seawater concrete. There’s been a general lack of knowledge about what the Roman model could produce
— via redwolf.newsvine.com