Florida DOT Concrete Batchman/Operator Practice Exam

How long must coarse aggregate stockpiles be sprinkled prior to batching FDOT concrete?

1. 12 hours

2. 24 hours

3. 48 hours

4. 72 hours

The correct answer is: 24 hours

Coarse aggregate stockpiles must be sprinkled for 24 hours prior to batching FDOT concrete to ensure that the aggregates are adequately saturated. This practice is crucial because it helps to prevent the absorption of water from the concrete mix by the dry aggregates, which can lead to a lower water-cement ratio than intended. A consistent water-cement ratio is vital for achieving the desired strength and durability of the concrete. Inadequate wetting time could lead to issues such as workability problems or decreased strength in the final product. Therefore, the specified 24-hour time frame is a standard requirement to promote optimal performance in concrete mixes.