Rutting resistance, fatigue properties and temperature susceptibility of nano clay modified asphalt rubber binder

In this study, rutting performance, fatigue response and, rheological properties of CRMN (Crumb Rubber Modified Nano-clay) binders were investigated using the Multiple Stress Creep and Recovery (MSCR), Linear Amplitude Sweep (LAS) and, Superpave tests. The physical and rheological tests indicate that adding nanoclay (NC) to asphalt rubber binder (ARB) can decrease temperature susceptibility and improve the aging resistance and rheological properties of ARB. MSCR test results show that the addition of NC reduces the permanent strain and increases the rutting resistance of ARB samples. In addition, the GTR15%+NC4% sample has the best rutting resistance, which improves performance grade from PG 58S-22 to PG 70H-28. LAS test indicated that the presence of a polymer network in ARB at low strain increases the fatigue life, however, increasing the strain causes the slipping and destruction of the polymer network. The addition of NC led to a delay in the oxidation process and improve the aging resistance, hence increasing fatigue life of ARB binders. Finally, the ANOVA and Tukey analysis showed that increasing GTR and NC have a considerable effect on rutting performance, PG temperature range and temperature susceptibility of ARB. (C) 2020 Elsevier Ltd. All rights reserved.