Congrui Jin: What if cracks in concrete could fix themselves?

Concrete is the most widely used construction material in the world. It can be found in swathes of city pavements, bridges that span vast rivers and the tallest skyscrapers on earth. But it does have a weakness: it's prone to catastrophic cracking that has immense financial and environmental impact. What if we could avoid that problem? Congrui Jin explores how to create a more resilient concrete. [TED-Ed Animation by Aeon Production].