Evaluation of Mechanistic Properties of Hot-Mix Asphalt Containing RecycledAsphalt Shingles for Use in the Pacific Northwest Coastal Region

摘要

Recycled Asphalt Shingles (RAS) contain asphalt cement and high quality aggregate that may be a usefulrnsupplement to virgin aggregates and asphalt cements. Metro Vancouver initiated a study to evaluate thernsustainability of using RAS as an additive in Hot Mix Asphalt (HMA), including environmental andrneconomic impacts, as well as technical performance.rnThe technical phase of this study focuses on the performance evaluation of HMA containing RAS. Sixrnmix types were included in the study. Besides a control mix incorporating only new materials, variousrnpercentages of RAS and Reclaimed Asphalt Pavement (RAP) were added to other mixes, with arnrejuvenator also added to some mixes. The asphalt mix performance testing included: dynamic modulus;rnresilient modulus; rutting resistance in the Asphalt Pavement Analyzer (APA); fatigue endurance in arnfour-point bending beam test; and low temperature cracking susceptibility in the Temperature StressrnRestrained Specimen Test (TSRST).rnThis paper presents the results and analysis of the first three tests. Due to mix hardening when RASrnand/or RAP were added, the study investigated the impact of adding a rejuvenator for softening. The mainrnobjective of the study is to determine the maximum acceptable amount of RAS and RAS/RAPrncombination that can be added to HMA.