Laboratory Evaluation of a Warm Asphalt Technology for Use in Virginia

摘要

Rising energy costs and increased environmental awareness have brought attention to the potential benefits of warm asphalt in the United States. Warm-mix asphalt (WMA) is produced by incorporating additives into asphalt mixtures to allow production and placement of the mix when heated to temperatures well below the 300 degrees F+ temperatures of conventional hot-mix asphalt (HMA). Potential benefits such as reduced plant emissions, workability at lower temperatures, extension of the paving season into colder weather, and reduced energy consumption at the plant may be realized with different applications. Trial installations of WMA, including two sections using the Sasobit WMA additive, have been investigated in Virginia. This study presents the results of laboratory testing to evaluate the performance of the mixtures used in the two Sasobit trial sections. The evaluation included comparisons of compactibility, volumetric properties, moisture susceptibility, rutting resistance, and fatigue performance between the HMA and WMA mixtures used in each section. Mixtures produced in the laboratory under conditions of varying temperatures and aging periods were tested, and the effects of temperature and aging were evaluated. The long-term performance of the two test sections was also modeled using the Mechanistic-Empirical Pavement Design Guide.