Correct Answer - Option 1 : 4 and 5
Concept:
The water in concrete has to perform the following two functions.
1. The water enters into chemical action with cement and this action causes the setting and hardening of concrete.
2. The water lubricates the aggregates and it facilitates the passage of cement through of voids of aggregate. This means that water makes the concrete workable.
The minimum quantity of water should be used to have reasonable degree of workability. The excess water occupies space in concrete and on evaporation, the voids are created in concrete. Thus the excess water affects the strength and durability of concrete.
Consistency and workability are relevant for ‘water-cement ratio.