Concrete The shrinkage of concrete is directly proportional to -

Answer is A & B
The water content plays a vital role in shrinkage of concrete because higher the water content higher the voids volume in concrete that Leeds the concrete to undergo for shrink during the process of hydration. Meanwhile the content of sand is also noticeable while designing a concrete mix. more the fines in concrete tends more shrinkage into it due to their accumulation at surfaces which provides the medium to water evaporation via capillary action; and obviously on top of the concrete section which we need to remove before next casting specially in vertical sections.

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