High modulus asphalt concrete: A state-of-the-art review

High modulus asphalt concrete (HMAC) was originally developed in France on the base course to resist the plastic deformation with the increasing heavy traffic. Although these mixtures were designed to serve as either base courses or binder courses, they were later extended to the wearing courses. This article first reviews the components of the high modulus mixture, its detailed design process and the pavement performances, including water stability, high temperature performance, and fatigue resistance and low temperature cracking resistance. The review finds that HMAC can be produced with binders from conventional hard grade binder, natural asphalt and plastic particles and low quality aggregates can be used with incorporation of modifiers. HMAC generally have improved water stability, better rutting resistance, reasonably well fatigue resistances but questionable thermal cracking resistance. Its application in the pavement structure can reduce the pavement layer thickness and thus save construction costs. The long term performance of HMAC needs further monitoring, especially for cold regions. (C) 2019 Elsevier Ltd. All rights reserved.