EVALUATION OF RUTTING SUSCEPTIBILITY OF MODIFIED ASPHALT BINDER

Abstract

This study presents experimental investigation results on evaluation of rutting resistance characteristics of asphalt binder containing two types of Styrene-Butadiene-Styrene (SBS). In the present study, pure asphalt binder (40-50 PEN) typically used in the middle and southern regions in Iraq was obtained from two sources and blended with different amounts of SBS, 3, 6, 9%, based on the total weight of the asphalt binder. The Dynamic Shear Rheometer (DSR) was used to evaluate the modifier asphalt binders at various temperatures, i.e., 25, 35, 50 and 60 °C. Good multiple linear relationships between log transformation of rheological properties and the amount of SBS asphalt modifier were obtained from this study. The SBS contents, temperatures and applied frequency are significant variables. It was found that the addition of SBS modifier generally increases the asphalt binder resistance against rutting. It was observed that an increase in SBS content causes an increase in G*/sinδ and enhanced the viscosity at high temperature by increasing the values of low and zero shear viscosity.