In order to obtain concrete of denser quality, the fine and coarse aggregates are properly graded. The grading of fine aggregates is expressed in terms of BIS test no. 480, 240, 120, 60, 30 and 15.
The grading of fine aggregates has a marked effect on the uniformity, workability and finishing qualities of concrete.
The grading of coarse aggregates may be varied through wider limits than those of sand without appreciable effect on the workability of concrete.
In general, it can be stated that it is difficult to provide satisfactory grading of coarse aggregates than of sand.