Effect of Reheating Plant Warm SMA on Its Fracture Potential

摘要

The primary objective of this study is to evaluate the fracture characteristics of stone mastic asphalt (SMA) with warm mix additives during its curing process. To this end, three SMA mixtures, prepared using different warm mix technologies (i.e. Evotherm additive, Sasobit additive, and foaming process) and one conventional SMA, were evaluated using the semi-circular bending (SCB) test. To investigate the aging effect due to mixture reheating, specimens tested in this study were compacted using both fresh and reheated plant mixtures. Specimens were tested at -12°C at 1 day, 3 days, 7 days, 3 weeks, 6 weeks and 12 weeks after compaction. The fracture energies of tested specimens were determined by calculating the areas underneath the loading-crack mouth opening distance (CMOD) curves obtained from the SCB test. This study revealed that the effect of curing time on the fracture potential of warm SMA is not statistically significant. In addition, reheating mixture for testing specimen preparation increases the fracture potential of both warm SMA and control SMA mixtures. The Evotherm SMA provided greater fracture potential than the control SMA when fresh plant mixtures were used to prepare the SCB test specimens. However, this relation was reversed when the SCB test was performed on specimens prepared using reheated plant mixtures, suggesting the importance of laboratory aging on laboratory test results.