Determination of rheological properties of cellulose oil palm fiber modified asphalt binder

Abstract

The use of Cellulose Oil Palm Fiber (COPF) in flexible pavements requires the better understanding of its effect on physical properties and rheological properties of COPF modified bitumen binders. The performance properties of COPF modified bitumen binder are influenced by the blending conditions and COPF content. The main objective of this study is to investigate the effect of various COPF content on the physical, rheological properties of penetration grade bitumen, 80-100 and 60-70. Laboratory tests undertaken comprises of viscosity test, penetration test, softening point test, short term ageing, Rolling Thin Film Oven Test (RTFO), long term ageing, Pressure Aging Vessel (PAV), and Dynamic Shear Rheometer (DSR) test. The DSR test was conducted under three conditions, un-aged, short term ageing, Rolling Thin Film Oven Test (RTFO), and long term ageing, Pressure Aging Vessel (PAV). The COPF was blended in 0.2, 0.4, 0.6, 0.8 and 1.0% with 0% as the control. The results showed that the addition of COPF has an effect on both the physical properties and rheological properties of COPF modified asphalt binders. The COPF modified asphalt binder showed an increasing viscosity and softening point temperature with increasing COPF content. Penetration decreases as the COPF increases for both binders. The complex shear modulus G*, rutting factor (G*/sin d) and fatigue factor (G*sin d) show significant improvement for the modified samples compared to unmodified samples. The results indicated that the COPF modified bitumen binder has high potential to resist performance (rutting) deformation and resist performance fatigue cracking than the unmodified sample. The maximum temperatures beyond which rutting will occur, is 64°C for modified 80-100 un-aged and short term aged binder, and 70°C for modified 60-70 un-aged and short term age binder. The minimum temperature below which fatigue cracking will occur is 31°C for modified 60-70 binder, while 80-100 binder can resist fatigue cracking under all test temperatures considered in this study. The COPF content of 0.4 to 0.6% gives the best rutting resistance and fatigue resistance under all conditions in this study