Emily Chan
“If the Romans put so much effort into making an outstanding construction material…why would they put so little effort into ensuring the production of a well-mixed final product?”
The team analyzed 2,000-year-old mortar samples from a city wall in the ancient city of Privernum, Italy.
They found that the technique of “hot mixing” was employed to produce concrete of an incredibly durable nature. The Romans combined quicklime, water, and volcanic ash at high temperatures.
Lime is a material rich in calcium, and it was used to mitigate erosion from water on roads and buildings.
Any tiny cracks in the concrete would recrystallize as calcium carbonate when exposed to water, filling the cracks with a glue-like substance. As a result, the cracks can be healed before they spread.
“It’s exciting to think about how these more durable concrete formulations could expand not only the service life of these materials but also [improve] the durability of 3D-printed concrete formulations,” Masic said.
