Question-

Q1 What do you understand by the term durability? Compared to other considerations, how much importance should be given to durability in the design and construction of concrete structures?

Q2 How would you define the coefficient of permeability? Give typical values of the coefficient for (a) fresh cement pastes; (b) hardened cement pastes; (c) commonly used aggregates; (d) high-strength concretes; and (e) mass concrete for dams.

Q3 How does aggregate size influence the coefficient of permeability of concrete? List other factors that determine the permeability of concrete in a structure.

Q4 With respect to frost damage, what do you understand by the term critical aggregate size? What factors govern it?

Q5 Discuss the factors that influence the compressive strength of concrete exposed to a fire of medium intensity 650 C, short-duration exposure). Compared to the compressive strength, how would the elastic modulus be affected, and why?