ABSTRACT
Concrete is composed of a mixture of fine aggregate, usually sand, coarse aggregate e.g. uncrushed gravel, a matrix or binding material, usually Portland cement, and water.
FINE AGGREGATE
May be natural sand dug f from pits or dredged from river beds, or artif ficial sand obtained by crushing stone or gravel. Sand for concrete should be clean, well graded and not contain an excess of fine, dusty particles.
