The objective of this research effort is to provide this collaborative demonstration by comparing laboratory and field performance of at least two mixtures each with a pair of MnROAD test sections. This research will demonstrate the benefits of adequately quantifying binder availability from RAM and thus provide guidelines for their efficient use.ĭifferent methods to quantify recycled binder availability will be explored and compared in a likely forthcoming NCHRP research project (based on #1 ranking from AASHTO COMP), but demonstration of the effects of adequate quantification of recycled binder availability in the field will be needed for implementation. These poor-performing pavements cost agencies due to reduced life and increased maintenance expenditures.
For example, if you are planning a bathroom project and there are going to be a lot of tile samples involved you may want to just go with a box type of system (or at least have a box handy to corral the samples). Thus, the assumption of 100% availability leads to less overall effective binder content, yielding a dry mixture with insufficient coating that may be difficult to compact and exhibit inadequate durability and cracking performance in-service. Box The type of project you are tackling will usually dictate your off-line organizing system. In reality, the amount of recycled binder available is somewhere between 0% availability and near 100% availability, with lower availability for heavily aged RAP or RAS binder and mixtures produced at lower temperatures. AASHTO guidance on the design of asphalt mixtures with RAP and/or RAS assumes that 100% of the recycled binder is available to blend with virgin binder and any additives such as recycling agents or warm mix asphalt (WMA) products. The use of recycled materials is growing due to economic and environmental benefits, yet there is no accepted method to quantify or account for the effective binder content available from these materials that represents larger fractions as RAM contents increase. The objectives of this research effort are to promote sustainability and ensure adequate performance, there is a need to consider the amount of asphalt binder available from recycled asphalt materials (RAM), including reclaimed asphalt pavement (RAP) and recycled asphalt shingles (RAS).