Evaluation of Performance Properties of Asphalt Mixture Containing SBR & Nanoclay

Nanomaterials have indicated a hopeful capacity in improving the behavior of pavement. As hot mix asphalt is a viscoelastic material, several distresses were occurred during their life time. Furthermore, steel slag was used to enhance the properties of mixture because of its outstanding physical properties. This research evaluated the effect of nanoclay and Styrene Butadiene Rubber (SBR) on performance behavior of bitumen and high and intermediate temperature performance of SMA mixtures containing steel slag aggregate. Through this paper, the AC-60/70 and AC-85/100 penetration grade bitumen’s were used as base bitumen. Moreover, SBR (0%, 2%, 4%, 6%, 8% and 10% by weight of binder), and nanoclay (0%, 1%, 2%, 3%, 4%, and 5% by weight of binder) were used as a mixture modifier. For evaluating the performance behavior of bitumen, the rotational viscosity, Dynamic Shear Rheometer (DSR), and Bending Beam Rheometer (BBR), Multiple Stress Creep Recovery (MSCR), and linear Amplitude Sweep (LAS) tests were implemented. Moreover, Resilient Modulus (Mr), Indirect Tensile Strength (ITS), dynamic creep, wheel track, and Four Point Beam Fatigue (FPBF) tests were performed to investigate the performance of mixture samples. To analyze the data statistically, two-factor analysis of variance (ANOVA) is evaluated. The rheological behavior test outcomes showed that the utilization of NC/SBR additive results in an enhancement in the rutting and fatigue resistance of binders. The utilization of NC decreases the low-temperature resistance of binders, while SBR improves the bitumen’s low-temperature resistance. Storage stability test outcomes reveal that utilization of NC enhances the storage stability of binders. Also, the application of SBR leads to enhance phase separation. The MSCR test results demonstrate an enhancement in the high-performance temperature of the virgin binder at different stress levels by the addition of NC/SBR. Moreover, the utilization of NS improves the rutting strength of samples. Based on the LAS test outcomes, the utilization of NC/SBR additives improves the fatigue properties of the asphalt binder. The mixture test results reveal that using NC/SBR increases the permanent deformation resistance, MR, ITS, fracture energy, and intermediate temperature properties of specimens.