(CNN)It’s the world’s most popular building material, and ever since the Romans built the pantheon from it some 2,000 years ago, we’ve been trying to find ways to make concrete more durable.

No matter how carefully it is mixed or reinforced, all concrete eventually cracks, and under some conditions, those cracks can lead to collapse.

https://edition.cnn.com/2015/05/14/tech/bioconcrete-delft-jonkers/index.html