North Carolina Building Contractor License Practice Exam

Concrete must be maintained at a temperature of at least 50 degrees in moist conditions for how many days after placement?

1. 1

2. 2

3. 3

4. 7

The correct answer is: 2

Concrete should be maintained at a temperature of at least 50 degrees Fahrenheit in moist conditions for at least two days after placement to ensure proper curing. During this critical period, the hydration process occurs, allowing the concrete to gain strength and durability. Curing is essential because it facilitates the chemical reaction between the cement and water, known as hydration, which is vital for developing the concrete's final properties. Maintaining the temperature and moisture level helps to prevent issues such as cold joints, cracking, and low strength, all of which can occur if the concrete dries out or if temperatures drop too low too quickly. The two-day timeframe is based on industry standards that ensure sufficient time for the concrete to cure to a point where it can withstand normal conditions without risk of damage.