Definition
Concrete curing is the process of maintaining adequate moisture and temperature in freshly placed concrete to allow proper cement hydration. Proper curing significantly increases concrete strength and durability. Curing should begin immediately after finishing and continue for at least 7 days for most applications. Methods include water spraying, wet coverings, curing compounds, and plastic sheeting.
Formula
At 70degreesF (21degreesC), concrete reaches approximately 70% of its 28-day strength in 7 days. For each 10degreesF decrease, curing time doubles. Concrete kept below 40degreesF may never reach design strength without heated curing.
Example
Curing Schedule Example
A typical driveway pour at 75degreesF should be kept moist for 7 days using a curing compound or wet burlap. The surface can be walked on after 24-48 hours, but vehicles should wait 7 days. In hot weather (90degreesF+), mist the surface hourly for the first 24 hours to prevent cracking from rapid evaporation.