ABSTRACT

Recently, there is a growing interest in increasing content of reclaimed asphalt pavement (RAP) material in the production of Hot Mix Asphalt (HMA) pavements to further reduce material costs and to preserve non-renewable resources. This study aims to evaluate the long-term performance of high RAP mixtures containing various softening oils. Both petroleum-based and bio-based oils were applied in preparing the 30% RAP and 50% RAP mixtures. The mixtures were subjected to the short-term oven aging (4 h), long-term oven aging (8 h), and extended-term aging (16 h) in the laboratory. Their performance, including the rutting, fatigue cracking at intermediate temperature, and low temperature cracking, were measured and compared with the control mixtures. The results indicate that the softening oils in this study can be used to produce asphalt mixtures containing high percentages of RAP with similar performance to a virgin mixture utilising the same aggregates and mixture design. In addition, the results show that making decisions to compare, qualify, or otherwise accept mixtures using the short-term aging results alone can be very risky. It is clearly shown in this study that relative ranking of mixture performance can change based on the level of aging.

摘要

最近，人们越来越关注在热混合沥青（HMA）路面生产中增加再生沥青路面（RAP）材料的含量，以进一步降低材料成本并保留不可再生资源。这项研究旨在评估含有各种软化油的高RAP混合物的长期性能。石油基和生物基油都用于制备30％RAP和50％RAP混合物。在实验室中，对混合物进行了短期烘箱老化（4 h），长期烘箱老化（8 h）和长期烘箱老化（16 h）。测量了它们的性能，包括车辙，中温疲劳裂纹和低温裂纹，并与对照混合物进行了比较。结果表明，本研究中的软化油可用于生产含有高百分比RAP的沥青混合料，其性能与使用相同集料和混合料设计的原始混合料相似。此外，结果表明，仅使用短期老化结果来做出比较，鉴定或以其他方式接受混合物的决策可能会非常冒险。这项研究清楚地表明，混合物性能的相对排名可以根据老化程度而变化。