Question

Which of the following statements is NOT true with regard to high volume fly ash concrete (HVFA)?
1. HVFA is to be cured effectively and for shorter duration than ordinary concrete.
2. As the water content is low in high volume fly ash, the bleeding is very low and often negligible.
3. The properties of HVFA concrete are largely dependent on characteristics of cement and fly ash.
4. HVFA concrete should be properly protected from premature drying by properly covering the surface.

Answer 1

Correct Answer - Option 1 : HVFA is to be cured effectively and for shorter duration than ordinary concrete.

 Concepts:

High volume fly ash concrete is a concrete where a replacement of 50 to 60 percentage of cement is made with the usage of fly ash. This fly ash may be mixed at the time of cement clinker formation or can be added in concrete as an admixture.

The followings are some characteristics of High Volume Fly ash Concrete:

1. Low heat of hydration and thermal shrinkage.

2. Longer Curing period. Minimum of 7 days of moist-curing is required.

3. Resistance to corrosion, resistance to alkali aggregate reaction, resistance to sulfate attack.

4. Properties like compressive strength, flexural strength, modulus of elasticity and split tensile strength are improved.

5. Applications: Dam Construction, Pavement Construction