How Does Concrete Stay Strong for Centuries?

When you pour concrete, it looks like a solid block almost right away. But deep inside, tiny chemical reactions are still happening. These reactions create tiny threads that act like glue.

Imagine if your cookies could heal themselves when they crack. Concrete does something similar using minerals found in the air and water. As these minerals settle into small holes, they make the concrete tougher without anyone needing to fix it.

Old buildings from long ago are still standing because this process never really stops. It is like a slow-motion repair job that keeps going for hundreds of years.