The concrete that makes up so much of our world is usually local in origin. To keep costs low, engineers use locally-sourced ingredients to make it. But not all ingredients perform the same.
In the decades since concrete’s widespread adoption, engineers have discovered that some components in the concrete are prone to chemical reactions that cause the concrete to expand over time. For big infrastructure projects like a mid-twentieth century dam, this sparks a conundrum: how can we deal with expanding concrete without losing out on years of the project’s planned lifetime?
To find out, see what Grady learned about the Tennessee Valley Authority’s clever method for relieving a dam’s stress. (Video and image credit: Practical Engineering)
