GOALI: Nanoscale Testing and Molecular Modeling of Aging in Asphalt

University Of New Mexico, Albuquerque NM

Investigators

Abstract

Asphalt aging is a complex process in which asphalt binders undergo important modifications of their structure and composition through processes such as oxidation, formation/breaking of weak bonds (chemical aging), ordering of similar molecules, evaporation of volatiles (physical aging) due to temperature, pressure, air, and other environmental factors. These modifications have dramatic effects on binder and mixtures? mechanical properties such as stiffness, harness, adhesion, and cohesion. Understanding how and what structural modifications affect the asphalt binder and mixtures? mechanical properties has remained unexplored, largely because these modifications occur at the atomic to molecular scales. This research offers a novel approach to understating the link between asphalt molecular structure and mechanical behavior through nanoscale experimentation and advanced molecular modeling. In this research, molecular dynamic models will be developed, validated, and employed to predict rheological and mechanical properties determined in the laboratory using nano experimentation, in addition to other traditional methods. This project is an integration of asphalt chemistry and mechanics, which will be integrated in an educational program that will improve the quality of engineering education. The molecular dynamics simulation will be supported through industry collaboration, which will strengthen the PI?s on-going research activities, and benefit the industry from broadening its product applications. This study may result in a general understanding of aging at a molecular scale, which is applicable to a wide range of construction materials. The integration of research and teaching will be addressed by involving graduate students, increasing diversity in engineering education, outreaching to high school students, development of new courses, and broad dissemination of research results.