In a field evaluation of vibratory rollers, an end-result specification based on a statistical analysis of densities obtained on previous construction projects indicated 98 percent of laboratory density (Marshall) to be desired for Bituminous Concrete, Class I Base. The minimum average of 5 density tests was set at 96.4 percent. Conventional rollers, vibratory rollers, and combinations thereof were qualified on the basis of density-growth curves determined on one or more 1000-foot test sections. An overall average compaction of 97.8 percent of Marshall density was obtained on the Cumberland Parkway project. Similar controls initiated on the Green River Parkway project were discontinued.

Report Date


Report Number

No. 362

Digital Object Identifier



The contents of this report reflect the views of the author who is responsible for the facts and the accuracy of the data presented herein. The contents do not necessarily reflect the official views or policies of the Kentucky Bureau of Highways, This report does not constitute a standard, specification, or regulation.