Quantitative Effect of Elastomeric Modification on Binder Performance at Intermediate and High Temperatures

An experimental study was conducted to characterize the dynamic mechanical properties of elastomer-modified asphalt binders at intermediate and high temperatures. Two types of elastomeric modifiers, styrene-butadiene-styrene (SBS) and styrene-ethylene/butylene-styrene (SEBS), were used at three different concentrations. Short-term aging and long-term aging were simulated by the rolling thin film oven test and the pressure aging vessel test, respectively. A dynamic shear rheometer was used to conduct frequency sweeps at temperatures ranging from 5°C to 75°C in increments of 10°C. Two fitting models were introduced to describe the variation of the selected parameters with temperature. An investigation of the resulting isochronal plots indicated that polymer modification is effective in increasing rutting resistance at high temperatures and fatigue resistance at intermediate temperatures. It was also found that SBES improves the binder rutting resistance more than SBS. However, SBS was found more effective in improving the binder fatigue resistance at intermediate temperatures.