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The following statements (S1, S2, S3) pertain to mass concreting. Which of the following statements are correct? S1: The materials preferred for mass concrete are: Portland cement with low heat of hydration, Pozzolanas, Aggregates (coarse and fine), Water, Admixture, Coolants. S2: Slump of mass concrete shall be the same or more than ordinary concrete work. S3: Concrete with a low water cement ratio, correctly consolidated and properly cured provides durability to mass concrete work.

The following statements (S1, S2, S3) pertain to mass concreting. Which of the following statements are correct? S1: The materials preferred for mass concrete are: Portland cement with low heat of hydration, Pozzolanas, Aggregates (coarse and fine), Water, Admixture, Coolants. S2: Slump of mass concrete shall be the same or more than ordinary concrete work. S3: Concrete with a low water cement ratio, correctly consolidated and properly cured provides durability to mass concrete work. Correct Answer S1 and S3 only

Concepts:

Definition: In general, mass concrete is defined as that concrete which requires is special attention to take care of thermal stresses that may arise in concrete due to the liberation of the heat of hydration of cement and the ensuing volume changes.

Examples: Pouring of large volume of concrete such as in Gravity dams, even medium pores of  high strength concrete  such as in piers.

Material: Portland cement with low heat of hydration, Pozzolana or fly ash, Aggregates (coarse and fine), Water, Admixture, and Coolants (chilled water).

Features:

1. It should be water tight.

2. Slump – 0 – 50 mm; i.e. less than that of ordinary concrete.

3. Low water cement ratio, consolidated and properly cured provides durability to mass concrete work

4. In hot weather conditions, the temperature of this concrete should be controlled between 5 °C and 20°C.

Related Questions

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