The two variables that most influence the behavior of asphaltic concrete pavements are subgrade modulus and thickness of the asphaltic concrete. Other significant variables are: temperature of the asphaltic concrete, asphaltic concrete modulus, frequency of the dynamic loading, asphalt content by weight in mix, and voids in the asphaltic concrete mix.

During a series of Road Rater tests on a experimental pavement in Kentucky, deflection test data varied widely from expected values. Test data reported by Kallas and Riley permitted the development of an equation relating asphaltic concrete modulus to its temperature and to the frequency of loading. However, after deflection data were adjusted for temperature and frequency, the variation was still greater than expected. Construction records for each test station were examined; the void content and asphalt cement content of the mix were found to vary considerably.

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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 Department of Transportation, the Federal Highway Administration, nor of the University of Kentucky. The report does not represent a standard, specification, or regulation.

Offered for publication to the 1982 Annual Meeting The Association of Asphalt Paving Technologists (February, 1982).