Low Temperature Performance of Superpave Recycled Hot Mixtures in Ontario

One of the effects of climate change is the drop in the extreme temperature during winter season. The impact that this phenomenon has on pavement performance is a concern, especially for the Hot Mix Asphalt (HMA) surface layers. The increasing use of sustainable techniques, like the addition of Reclaimed Asphalt Pavement (RAP), poses a challenge to enduring extremely low temperatures. This study examines the performance of typical Ontario Superpave surface course HMA to thermal cracking. Thermal Stress Restrained Specimen Tests (TSRST) and Disk-Shaped Compact Tension Tests (DC(T)) were conducted on six laboratory prepared hot mixtures with varying RAP contents and Asphalt Binder Performance Grade (PG). The results suggest that the Recycled Hot Mixtures (RHM) do not always withstand the expected critical temperatures, but they could exhibit a lower impact in fracture strength when the extreme low temperature drops by 6°C.