For concrete works in sea water or exposed directly along the sea coast, the minimum grade of concrete recommended by IS 456: 2000, for Plain Concrete and Reinforced Concrete are, respectively:

For concrete works in sea water or exposed directly along the sea coast, the minimum grade of concrete recommended by IS 456: 2000, for Plain Concrete and Reinforced Concrete are, respectively:

a) M10 and M20

b) M20 and M30   (Ans)

c) M15 and M25

d) M25 and M40