Long-term ageing influence on rheological characteristics of asphalt binders containing carbon nanoparticles

Abstract
Nano-sized particles have been used in numerous applications to improve properties of various materials. The utilisation of nanotechnology in civil engineering area is relatively new and its use and applications are expected to increase rapidly. The objective of this study was to investigate and evaluate the rheological properties of binders containing various percentages of carbon nanoparticles after a long-term ageing process. The experimental design for this study included the utilisations of five binder sources (three grades of PG 64-22, PG 64-16 and PG 52-28) and four nano percentages (0.0, 0.5, 1.0 and 1.5% by weight of the virgin binder). The rheological characteristics of these pressurised aged vessel (PAV) binders were tested including G* value, creep and creep recovery, and frequency and amplitude sweep at an intermediate temperature and deflection, stiffness and m-value at a low temperature as well. The results of the experiments indicated that the addition of nanoparticles does not increase the G* values and does have an obvious effect on complex modulus, phase angle under a frequency sweep test. However, nanoparticles have a slight effect on creep angle and compliance of a binder. Moreover, at a low tested temperature, the experimental results indicate that the nanoparticles have no effect on deflection, stiffness and m-value of PAV residue. Furthermore, statistical analysis indicates that the asphalt binder source and grade rather than nanoparticles play a key role in determining the rheological properties