1.1 This specification covers quality-controlled graded aggregates that, when hauled to and properly spread and compacted on a prepared grade to appropriate density standards, may be expected to provide adequate stability and load support for use as highway or airport bases or subbases.

Note 1-The engineer is cautioned to provide appropriate construction specifications to ensure compaction to an extent that further densification from traffic loadings on the completed pavement will be insignificant. The method suggested is to require compaction on a firm foundation of a short control strip of the material at a suitable moisture content, by means of vibratory or other proven effective rollers or tampers, until no further increase in density results. Compaction requirements should ensure that an average density of certain appropriate percentages of the control strip maximum density be achieved on the balance of the job; for base courses, 98% is suggested as the minimum average requirement.

1.2 The values stated in inch-pound units are to be regarded as the standard. The SI equivalents shown in parentheses may be approximate, except with regard to sieve sizes and size of aggregate as determined by the use of testing sieves, in which case the standard SI designation shown in parentheses is the standard as required by Specification E-11.