General Contractor Practice Exam

What effect does curing concrete have?

1. Increases initial set time

2. Improves strength and durability

3. Reduces water content

4. Causes faster drying

The correct answer is: Improves strength and durability

Curing concrete primarily serves to enhance its strength and durability by providing the necessary moisture for hydration, which is the chemical reaction between cement and water that leads to the hardening of the concrete. Proper curing ensures that the concrete remains at an adequate temperature and moisture level for a sufficient duration, typically for at least seven days, although this can vary depending on the specific concrete mix and environmental conditions. When concrete is cured effectively, it can achieve its design strength and optimal performance characteristics, leading to a more durable finished product. This durability translates into increased resistance to cracking, weathering, and chemical attack, making the cured concrete capable of withstanding various environmental stresses throughout its lifespan. The other options relate minimally to the purpose and roles of curing. For instance, curing does not inherently increase the initial set time; rather, it helps maintain the right conditions for concrete to set properly. While curing does influence water content during hydration, it does not reduce the water content; rather, it protects the existing moisture. Additionally, proper curing practices do not accelerate drying; instead, they prevent rapid evaporation of moisture, which can be detrimental to the concrete's final properties.