Abstract
Waste materials in asphalt mixtures have garnered significant interest due to environmental concerns and the necessity for sustainable infrastructure. This study evaluated the performance of a waste material-based hybrid asphalt mixture, including palm oil fuel ash (POFA), garnet waste, and sawdust. Numerous physical tests were conducted to examine the hybrid asphalt mixture characteristics, such as penetration, softening point, and viscosity assessments. A Marshall stability and Dynamic Shear Rheometer (DSR) was also performed to assess the stability and rheological characteristic of the mixture. Consequently, the hybrid asphalt mixture demonstrated favourable outcomes in improving the hot mix asphalt characteristics. These findings suggested that the hybrid contents (0% as control, 3%, 6%, and 9%) produced a significant performance impact on the hybrid asphalt mixture. The 6% hybrid asphalt mixture yielded the highest stability, delivering a Marshall stability value of 22.33 kN and suitable ageing resistance of asphalt samples due to the high sensitivity of the binder to the test temperature. Furthermore, the scanning electron microscopy (SEM) and atomic force microscopy (AFM) studies reported strong adhesion and interaction between the particles in the 6% hybrid asphalt mixture. This study effectively demonstrated that the waste materials (POFA, garnet waste, and sawdust) in the hybrid asphalt mixtures developed enhanced physical and mechanical characteristics. The results also indicated that the hybrid asphalt mixtures exhibited potential durability and performance in improving the longevity and efficacy of hot mix asphalts. Therefore, this study provided evidence of effective and sustainable construction practices in asphalt pavements. Further research on waste components in asphalt mixtures should also be investigated to enhance their overall efficacy.