Analyzing Behavior of Polymer Modified Asphalt Using Master Curve Approach

In Pakistan, asphalt pavements are experiencing a high rate of deterioration due to rutting and fatigue cracking. These problems arise in asphalt pavements due to the use of improper binder characterization and mix design. It is believed that polymer modification can be employed to improve binder ductility and durability. Therefore, the objective of this study is to analyze the behavior of virgin and polymer modified asphalt at a range of temperature and rate of loading. Two virgin and seven polymer modified asphalt (PMA) samples were tested using Dynamic Shear Rheometer. Master curves were developed for complex shear modulus by applying a shift factor to log of time at each temperature to the reference temperature. The major finding is that a decrease in the temperature susceptibility was observed for PMA samples; that is relatively lower stiffness at lower temperature and relatively higher stiffness at higher temperature. These polymer modification results are beneficial in improving the performance of flexible pavements.