What is concrete "segregation"?

Concrete segregation refers to the separation of concrete constituents, which can occur when the heavier materials, such as coarse aggregates, settle to the bottom of the mix while the lighter components, like water and fine aggregates, rise to the top. This phenomenon can lead to an uneven distribution of materials, resulting in areas of poor strength and durability in the finished product.

When segregation occurs, it can negatively affect the workability, strength, and overall quality of the concrete. Proper mixing and handling procedures are essential to minimize segregation, ensuring that the concrete has uniform consistency throughout the batch. This understanding is crucial for flatwork finishing, as consistency in the material directly impacts the finish and performance of the concrete surface.

In contrast, mixing different concrete qualities, adding air, or referring to the hardening process does not define segregation, thus clarifying why those options are not accurate descriptions.