Mechanistic Evaluation of the Long Term Performance Characteristics of Warm Mix Additives in Modified Asphalt Mixtures

Abstract

The immediate benefit of producing Warm Mix Asphalt (WMA) mixtures is the reduction in the consumption of energy required to produce the traditional hot mix asphalt (HMA). WMA additives also improve workability and compactability of mixtures to a point where they can be produced at lower temperatures. With the decreased production temperatures comes the benefit of reduced emissions, fumes, dust production and odors, as well as an extended mix haul distance. This study evaluated the long term performance of two different WMA technologies with neat, polymer modified and terminal blend tire rubber asphalt mixtures, designed according to Nevada Department of Transportation (NDOT) and California Department of Transportation (Caltrans) specifications using the Hveem mix design, using one source of aggregates sampled in two different batches from a local quarry. An experimental program was designed to cover the impact of WMA additives on the performance characteristics of the different mixtures using the flexural beam fatigue test and a mechanistic analysis of mixtures in simulated pavements using a 3D-Move analysis on two pavement structure; thin (100 mm) and thick (200 mm). The findings will be presented in the paper below.