How is concrete workability typically measured?

Concrete workability refers to how easily freshly mixed concrete can be placed, compacted, and finished without segregation or bleeding. The slump test is the most widely used method for measuring the workability of concrete. This test involves filling a conical mold with concrete, lifting the mold, and measuring how much the concrete 'slumps' or settles. The amount of slump indicates the consistency and workability of the mix—the greater the slump, the more workable the concrete.

A viscosity test measures the resistance of a fluid to flow, which does not directly correlate to the practical application of concrete workability. Similarly, a penetration test often relates to the hardness or firmness of a material rather than its workability, and a compaction test measures the density of soil or concrete rather than its ease of handling and placement. Hence, the slump test is specifically designed to assess workability in concrete and is crucial for ensuring that the mix can be successfully placed and finished.