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Mar 2023
13m 12s

Rome wasn't built in a day, but they sur...

NPR
About this episode
The Roman Colosseum is a giant, oval amphitheater built almost two thousand years ago. Despite its age and a 14th century earthquake that knocked down the south side of the colosseum, most of the 150-some foot building is still standing. Like many ancient Roman structures, parts of it were constructed using a specific type of concrete. Scientists and engineers have long suspected a key to these buildings' durability is their use of this Roman concrete. But exactly how this sturdy concrete has contributed to the architecture's strength has been a mystery to researchers across the globe.

A team of interdisciplinary researchers have recently discovered one answer to why these ancient Roman buildings have weathered the test of time — while many modern, concrete structures seem to crumble after a few decades.

The answer: self-healing concrete.

Curious about other new discoveries or potential climate solutions scientists are researching? Email us at ShortWave@NPR.org.

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