What does "slump" indicate in concrete tests?

"Slump" is a crucial measurement in concrete tests, specifically assessing the workability and consistency of fresh concrete. This measurement is derived from a standardized test in which a cone-shaped mold is filled with freshly mixed concrete, and then the cone is removed. The amount the concrete settles or "slumps" indicates how workable the mix is. A higher slump typically suggests that the concrete is more fluid and easier to work with, making it suitable for certain applications. Conversely, a lower slump indicates a stiffer mix, which might be better for structural applications requiring less flow.

Assessing the slump allows concrete professionals to ensure that the mixture has the appropriate consistency for the intended application, whether it is for flatwork, foundations, or other structures. Adjustments can be made to the mix design accordingly to achieve the desired workability. Thus, understanding slump is essential for proper concrete placement and finishing, leading to superior-quality results in concrete projects.