Repair efficiency evaluation for cracked asphalt mixture pavement in different ambient temperatures using bitumen and polymer concrete as repair materials

This paper studies the effect of crack repairing process on the behavior of pavement at four ambient low and medium temperatures ranging from −20 °C to 30 °C. Asphalt mixture samples in the shape of semi-circular bend (SCB) were tested in intact, cracked, and repaired conditions under tensile or opening mode of loading. Two adhesive types: namely pure bitumen and polymer concrete were used to repair the crack. To investigate the efficiency of the repair process, some indexes such as failure load, initial and post-failure energies, and failure patterns were evaluated using the intact and cracked SCB specimens. Failure patterns showed that in the repaired specimens with pure bitumen, the failure initiates from the mid-section (i.e., from the repaired zone), while in polymer concrete repaired specimens, the failure initiates far from the repaired zone. Experimental results also revealed that the temperature has a noticeable effect on the repair efficiency using bitumen adhesive. Indeed, for sub-zero temperature conditions, such repairing material partially provided acceptable integrity for the pavement compared to the intact asphalt mixture. But, for service temperatures greater than + 10 °C, repair with bitumen was inefficient. However, repair with polymer concrete was efficient in all temperatures, and the strength of specimens repaired by the polymer concrete was even higher than the intact specimen. Similar trends and results were also obtained for the work of failure indexes.