Enhancing Asphalt Mix Performance: The Impact of Iron Oxide and Zinc Oxide Nanoparticles on Bitumen Properties

This study aims to enhance the performance of asphalt mixes by improving the physical characteristics of bitumen across various temperatures. The focus is on the use of innovative modified bitumen to optimize both fundamental and rheological properties. Bituminous binders are tested with varying additive contents (0%, 0.5%, 1%, and 1.5% by binder weight), incorporating iron oxide and zinc oxide nanoparticles (NPs) into Grade (40/60) bitumen. A comprehensive range of testing methods is employed to evaluate the binders, including penetration, ductility, softening point, aging resistance under heat and air exposure, Dynamic Shear Rheometer (DSR), Bending Beam Rheometer (BBR), and direct tension test. The results demonstrate that the addition of iron oxide and zinc oxide NPs significantly alters the physical behavior of the binders, leading to increased viscosity and improved aging resistance. Notably, the modified bitumen shows an increased softening point and decreased penetration and ductility, indicating a hardening effect, while elastic recovery improves with higher additive percentages, enhancing flexibility. These findings provide valuable insights into the modification of asphalt binder and its impact on the performance of asphalt concrete mixtures, particularly in Hot Mix Asphalt (HMA) applications at elevated temperatures, highlighting the novelty of this approach.