Mechanistic - empirical pavement design guide implementation and pavement preservation strategies with asphalt rubber

Abstract

Paper presented at the 30th Annual Southern African Transport Conference 11-14 July 2011 "Africa on the Move", CSIR International Convention Centre, Pretoria, South Africa.

Asphalt-Rubber (AR) mixtures, with their great fleld performance, have received great attention from many transportation agencies world-wide. Current pavement design procedures do not specifically address the unique engineering properties that these mixtures offer. For example, the Mechanistic-Empirical Pavement Design Guide (MEPDG) did not include asphalt-rubber mixes as part of its calibration and Implementation in the USA. This paper addresses some issues on asphalt rubber mixtures implementation into the MEPDG. In addition, highlights of several studies conducted by the authors documenting benefits of the Asphalt Rubber Asphalt Concrete Friction Course (AR-ACFC) as a pavement preservation strategy. This includes results of laboratory materlal characterization tests, highway noise reduction, mitigation of daily thermal variances in Portland Cement Concrete pavements, improved skid resistance, reduced roughness, reduction of emission rates of tire wear per kilometer driven, and lower environmental Impact by having lower C02 emissions.