Redefining HiMA: an approach to performance based characterization

Abstract

Highly Modified Asphalt (HiMA) represents an advanced evolution of Polymer-Modified Asphalts (PMAs), engineered to meet the demands of high-stress pavement applications. Incorporating higher dosages of Styrene-Butadiene-Styrene (SBS) polymer, HiMA offers enhanced resistance to rutting, fatigue, and thermal degradation, surpassing the performance of conventional SBS-modified PMAs. Traditional methods of identifying HiMA, such as Fluorescence Microscopy (FM), rely on detecting phase reversal but fail to encompass broader performance attributes relevant to real-world applications.This study proposes a more holistic approach to HiMA classification, focusing on measurable parameters like softening point, penetration values, and Performance Grading (PG) under various aging conditions. By quantifying the SBS content necessary for significant PG shifts, the research establishes a clearer understanding of the transition from PMA to HiMA. These insights provide a robust framework for correlating SBS content with asphalt performance, bridging gaps in scenarios where only PG temperatures are specified, and enhancing the practical application of HiMA.