This test method provides an index value to the relative particle shape and texture characteristics of aggregates. This value is a quantitative measure of the aggregate shape and texture characteristics that may affect the performance of road and paving mixtures. This test method has been successfully used to indicate the effects of these characteristics on the compaction and strength characteristics of soil-aggregate and asphalt concrete mixtures.^{3 ,4 ,5 ,6}

1.1 This test method covers the determination of the particle index of aggregate as an overall measure of particle shape and texture characteristics.

1.2 The values stated in inch-pound units are to be regarded as the standard. The SI units given in parentheses may be approximate, except with regard to sieve size and size of aggregate, the standard SI designations shown in parentheses are the standard as stated in Specification E 11.

This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.