Functional durability evaluation of asphalt mixture containing ecologically friendly hydrophobic anti-icing additives

Abstract

The ecologically friendly hydrophobic anti-icing fillers have gained great prominence due to the increasing demand for the green environment. However, two major challenges are the durability of hydrophobic anti-icing performance and the pavement skid resistance when incorporated to asphalt mixtures. Therefore, the aims of this work are to introduce three new ecologically friendly hydrophobic anti-icing additives (EFHAAs), that is, Polytetrafluoroethylene (PTFE), Polyurea (PU) as well as Polyethylene wax microparticles (PEWMP) and to evaluate the durability of hydrophobic anti-icing performance and the skid resistance evolution rule. In detail, the long-term hydrophobic performance of EFHAAs was investigated by water droplets sliding time test. The long-term anti-icing performance was evaluated by ice-breaking test and water droplets condensation time test. In addition, the skid resistance evolution rule was studied through the sand patch method, British Pendulum Tester (BPT) as well as Walking Frictional Tester (WFT). Moreover, the consideration of long-term performance was achieved by simulating the actual service condition of the pavement through subjecting the specimens to 60d of outdoor exposure and 10,000 times of accelerated abrasion. The results obtained pointed out that the three EFHAAs can effectively enhance the hydrophobic and ice-suppression performance of asphalt mixtures. The durability of hydrophobic anti-icing performance of three EFHAAs can be ranked as PTFE > PU > PEWMP. Whereas the skid resistance of the mixture deteriorated due to the loss of partial pavement micro-texture caused by the addition of EFHAAs.