Water absorption is an important parameter of concrete. If water absorption is high, then the water cement ratio is also high, and the consumption of cement is high. If the silt percentage is high in fine aggregate, then the water absorption is also high but in washed manufacture sand the silt percentage is in limit as per IS 383-: 1970. Water cement ratio depends on water absorption. By experimental data we can see the water absorption of unwashed sand is between 2.5– 3% whereas in washed sand the water absorption is between 2 – 2.5%.
