Influence of herbal and mineral fillers on physical and rheological properties of bitumen

Abstract

Even though fillers such as Limestone Powder (LP), Hydrated Lime (HL), cement and ashes improve the performance of pure bitumen, application of Herbal Fillers (HFs) such as oat, wheat and potatoes provides a better mixture in mastic asphalt considering environmental protection problems. Therefore, the aim of this study is to investigate the performance of bitumen modified with HFs. Penetration, softening point, viscosity and dynamic shear rheometer tests are performed using 3 and 5 wt% of fillers in the bitumen. For a better comparison of the results, samples containing LP and HL fillers are also tested. The results show that HFs improves the softening point, viscosity and penetration index. The rutting parameter (Formula presented.) exhibits a significant improvement in dynamic shear rheometer test. However, its effect on the fatigue parameter (Formula presented.) is negative. In addition, the shape of the filler is an effective parameter. It was revealed that the performance of fibre-shaped filler is higher than that of spherical one. Oat is the most effective herbal filler, while potato one shows the worst performance. © 2020, © 2020 Engineers Australia.