When should curing of the concrete for the slab on grade and/or panels begin?

• A. After pour completely
• B. As soon as the finishers are done
• C. After 7 days
• D. After 24 hours

Answer: (B)

Starting curing right after finishing is essential because the surface is most vulnerable to moisture loss as soon as finishing ends. Hydration—the chemical reaction that hardens concrete—stays effective only if the concrete remains moist. If curing is delayed, the surface can dry quickly, increasing the risk of plastic shrinkage cracking and slower early strength gain. By beginning curing as soon as the finishers are done, you preserve moisture at the surface and allow continuous hydration, which improves durability and reduces cracking. Thus, curing should start immediately when finishing is complete, rather than waiting a full pour completion, 24 hours, or several days later.