Molecular Components and Molecular Modelling for Asphalt: A Review

Abstract

Asphalt is a complex, heterogeneous organic mixture increasingly used in modern pavement. With the rising traffic load and sustainable strategies, developing high‐performance asphalt materials becomes crucial, which relies on the understanding of the relationship between the physical chemical properties of asphalt and its constituent molecular components. This work aims to review the progress on the identification of asphalt molecular components, as well as different types of molecules being employed in various molecular dynamics simulations to assess the physical properties of asphalt. The state‐of‐the‐art techniques for the separation of molecular components for asphalt materials are first introduced, followed by common characterization techniques for asphalt molecules and microstructural features, which serve as the foundations for molecular modeling for asphalt materials. Various asphalt molecular models being employed in molecular dynamics simulations are summarised, covering pristine asphalt, modified asphalt, and aged asphalt. Different factors that impact the physical properties of asphalt as uncovered from these simulations are also discussed. This work provides a comprehensive overview on the molecular components of asphalt and the corresponding modeling as atomistic scale, which can guide the preparation of asphalt materials with on‐demand properties for sustainable development.