Effect of Gradation and Aged Binder Content of Reclaimed Asphalt Pavement (RAP) on Properties of Cold-Recycled Asphalt Mix

摘要

Cold-recycling of asphalt is an effective method enabling agencies to conserve valuable resources during rehabilitation of distressed roads. The objectives of this study are to improve the understanding regarding cold-recycled asphalt performance, investigate the impact of the Recycled Asphalt Pavement (RAP) gradation and RAP binder content on properties of the cold-recycled asphalt at given recycling agent and water content level, and evaluate the effect of recycling agent content and water content levels on the performance of Cold-Recycled asphalt. Various RAP sources with controlled gradations and five different asphalt content levels were mixed with emulsion at two different dosages and tested for performance properties; including Marshall stability and moisture susceptibility. The results show that at the early stages of curing the effect of gradation of the RAP is more important than the aged RAP binder content. Moreover, at this stage, increasing emulsion content improves wet stability and moisture susceptibility of the samples regardless of the RAP binder content and gradation of the cold-recycled mix.