General Contractor Practice Exam

Which factor is critical for ensuring proper curing of concrete?

1. Temperature and humidity

2. Wind speed

3. Concrete mix ratio

4. Type of formwork used

The correct answer is: Temperature and humidity

Ensuring proper curing of concrete is essential for achieving the desired strength, durability, and overall performance of the finished structure. Temperature and humidity play a critical role in this process. When concrete is poured, it undergoes a chemical reaction known as hydration, during which water combines with cement particles to form a strong bond. Warm temperatures can increase the rate of evaporation from the surface of the concrete, potentially leading to surface cracking if not managed properly. Conversely, if temperatures are too low, the hydration reaction can slow down significantly, delaying the curing process and potentially compromising strength if the concrete does not cure for an adequate period. Humidity also affects curing; high humidity can slow evaporation, while low humidity can speed it up. Thus, monitoring and controlling both temperature and humidity during the curing period are vital to ensure that the concrete remains moist and the hydration process continues effectively. While wind speed, concrete mix ratio, and type of formwork are important considerations in concrete construction, they do not play as direct a role in curing as temperature and humidity do. Wind can indeed accelerate moisture loss, but it is a secondary consideration compared to controlling the ambient conditions that directly impact hydration. The concrete mix ratio influences strength and durability but does not directly affect the curing process itself