The strength of aggregates is determined from one of the three tests :
Aggregate Impact Test
In which the aggregates in a mould are subjected to impact caused by dropping a hammer giving 15 blows, and finding the percentage of crushed material, known as the Aggregate Impact Value. For base courses, a limit of 40 per cent is specified and for surfacing courses, a limit of 30 per cent is specified. Figure gives the arrangement of the testing apparatus.
(All dimensions are in millimetres)
Figure: An Aggregate Impact Test equipment