Grading of Aggregates
The art of doing gradation (particle size distribution) of an aggregate as determined by sieve analysis is called grading of aggregate.
The grading of aggregate has a considerable effect on workability, uniformity & finishing qualities of plastic concrete which ultimately affec& other properties of hardened concrete.
Proportioning of Aggregates
The art of determining the quantities of the various ingredient so as to obtain densest and most economical concrete mix is called proportioning of aggregate.
The principle of proportioning of aggregates is that the smaller particles will fill up the voids between large particles. A well proportioned concrete mix requires a minimum amount of cement per unit volume.