Influence of polyethylene glycol (PEG) chain on the performance of epoxy asphalt binder and mixture

Abstract At low temperature, epoxy asphalt is a brittle material and presents insufficient resistance to deformation. In this research, a new approach was proposed by introducing PEG with number-average molecular weight (Mn) of 200,400, and 800 g/mol to improve the toughness of epoxy asphalt. The influence of PEG chain on the dynamic properties and hydrophilicity of epoxy asphalt binder, the mechanical properties and viscoelastic characteristics of epoxy asphalt mixture were investigated by experiments. The thermal stress of epoxy asphalt mixture containing PEG chains was analyzed by TSRST simulation. The results show that the performance of epoxy asphalt containing PEG with Mn of 200 g/mol is equivalent to that of commercial epoxy asphalt. With the Mn of PEG increasing, the low-temperature resistance, toughness, and hydrophilicity of binder enhance. Besides, the introduction of PEG chain has a slightly negative effect on the strength, high-temperature stability, and moisture resistance of epoxy asphalt mixture, while it has a significant improvement on low-temperature performance and toughness and a lower chance of thermal cracking damage. When PEG with Mn of 400–800 g/mol is introduced, epoxy asphalt mixture can be recommended for road and bridge deck pavement in severe cold regions.