Grading of Aggregates:

Well-graded aggregates with adequate contribution of all sizes of the aggregates have fewer voids as compared to poorly graded aggregates. For such well-graded aggregates more paste will be available for lubrication purpose hence, workability gets improved. Instead, one could acquire more dense concrete with least voids and that too by providing least compaction efforts.

Water Absorption of Aggregates

Water absorption of aggregates increases with the porosity of aggregates. So, porous aggregates will have greater demand of water hence; less water will be available for lubrication purpose which reduces the workability of concrete if this factor has not been taken into account in determining the quantity of water. Thus, sound/dense aggregates will provide better workability as compared to porous and lightweight aggregates.