FIVE-YEAR EXPERIENCE OF LOW-TEMPERATURE PERFORMANCE OF RECYCLED HOT MIX

The thermal cracking results of five recycled hot-mix (RHM) sites constructed between 1981 and 1983 during the early recycling program of the Ontario Ministry of Transportation are presented. The results are from laboratory and field evaluation, involving comparison between the two types of results and the use of McLeod's limiting stiffness criteria and fracture temperature method. The study confirms the common belief that RHM is less resistant to thermal cracking than non-recycled mixes. Fracture temperature method was found to be better than McLeod's limiting stiffness approach for evaluation of low temperature cracking. Recommendations to improve RHM low temperature performance are also made.