The effect of grading and shape on the bulk density of concrete aggregates*

Laboratory tests have shown that variation of grading within the limits permitted by the British Standard 882:1944 for concrete aggregates results in differences of as much as 12 lb/cu.ft. in the compacted bulk density of coarse aggregates, and 13 lb/cu.ft. in Class A and 31 lb/cu.ft. in Class B fine aggregates. It was also found that the bulk densities of different gradings of a rounded aggregate were between 5 and 10 per cent higher than those of the corresponding gradings of an angular aggregate with the same specific gravity.