Rheological and morphological evaluation of nanoclay modified asphalt binder

Abstract

The performance characteristics of asphalt can be improved by using nanomaterials. In this study, the effect of nanoclay as an additive on the performance features of the asphalt binder was assessed; this nanoclay was produced from montmorillonite modified with organic compounds and hexadecyltrimethylammonium bromide additive. The structural properties of the additive were investigated using X-ray diffraction analysis. The morphological structure and modification mechanism of modified asphalt binders formed by adding the nanoclay to the asphalt were determined by two analyses namely scanning electron microscopy and Fourier transform infrared spectroscopy, respectively. In addition, differential scanning calorimetry analysis was used in order to investigate the thermal properties of the additive and modified asphalt binders. The rheological and physical properties of the modified asphalt were measured using penetration, ductility, softening point, dynamic shear rheometer, rotational viscometer, rolling thin film oven test, and pressure-aging vessel. The results indicated that the additive increased the asphalt's consistency rutting, and short-term aging resistance, and decreased fatigue resistance after long-term aging. In addition, the optimal additive concentration to enhance the performance features of the asphalt binder was found to be 8% based on the experimental data.