Rheological Evaluation of Ageing Properties of SEBS Polymer Modified Bitumens

Abstract

Ageing of bitumen is an important cause of reduced durability of asphalt pavements. Therefore, the polymer modified bitumens are recommended to increase the durability of the material. In the present work, rheology has been applied to evaluate the properties of Styrene-Ethylene- Butadiene -Styrene (SEBS) polymer modified bitumen (PMB) to compare to the 35 / 50 penetration grade bitumen, before and after ageing. The effects of ageing on the physical and rheological properties of (PMB) were evaluated using SARA analysis, penetration test, softening point test and dynamic shear rheometer test (DSR). The binders were aged by Rolling Thin Film Over Test (RTFOT) and Pressure Ageing Vessel (PAV). The results showed that use of SEBS polymer reduces the ageing effect on physical and rheological properties of the bitumen binder as illustrated through lower ageing index of complex modulus and an increase in tang δ indicating that the SEBS polymer improve the ageing resistance of bitumen binder.