If there is uncertainty about the moisture content of aggregates, what should be done?

• A. Ignore moisture and rely on trial and error.
• B. Use dewatering only.
• C. Use aggregates with known moisture content and adjust batch water accordingly.
• D. Increase cement content.

Answer: (C)

When moisture content in aggregates is uncertain, the amount of water actually entering the concrete mix becomes unpredictable and can throw off the target water-cement ratio, which directly affects strength, durability, and workability. The best approach is to use aggregates with known moisture content and adjust the batch water accordingly so the overall water in the mix matches what the mix design specifies. This keeps the mix proportions consistent and the resulting concrete within specification.

Other options would lead to unpredictable results: ignoring moisture or relying on trial-and-error doesn’t guarantee the target w/c is met, and simply dewatering or increasing cement doesn’t reliably control the actual water balance or optimize material use.