Characterizing viscoelasticity and fatigue damage of complex polymeric material asphalt using molecular-scale dynamic modelling
Year: 2026
Type: article
Abstract: Molecular dynamics simulations are employed to investigate the nanoscale properties of asphalt binder, a polymer-based composite material. However, nanoscale nonlinear viscoelasticity and fatigue damage remain poorly understood, and molecular simulation parameters still lack a robust quantitative link to macroscopic mechanical performance. Progress in cross-scale prediction of asphalt mechanical properties is severely limited by the lack of molecular-scale methods to capture key parameters (e.g., dynamic modulus). This study develops a dynamic loading modelling algorithm to characterize the viscoelastic and fatigue damage behavior of the asphalt materials at the nanoscale. The results show that the dynamic modelling can obtain stable stress-strain data with characteristic viscoelastic hysteresis behavior. The simulated dynamic shear modulus master curves capture differences among molecular components and reproduce the relative magnitudes observed experimentally. Despite a nine orders of magnitude difference in temporal and spatial scales between the asphalt binder models and actual materials, high-frequency simulations deviate by less than 0.5 orders of magnitude from macroscopic data from the SHRP report. Under constant temperature and loading frequency, the asphalt molecular model exhibits the typical stage mechanical responses: linear viscoelastic, nonlinear viscoelastic, and fatigue damage. Input stress amplitudes of 0.4 GPa and 0.7 GPa serve as thresholds for these stages in the AAM-1 asphalt binder model. Energy dissipation remains nearly constant during viscoelastic stages but increases in the damage phase, accompanied by microstructural evolution such as void growth and increased fractional free volume, reflecting progressive structural degradation and reduced deformation resistance. These findings advance the understanding of molecular-scale dynamic mechanics in asphalt binder, provide quantitative insight into stage-specific viscoelastic and damage behavior, and offer a foundation for cross-scale constitutive modeling and prediction of macroscopic mechanical performance. • Developed a molecular simulation method to study asphalt viscoelasticity and fatigue. • Validated the time-temperature superposition principle at the molecular scale. • Dynamic modulus decay and energy dissipation align with macroscopic behavior. • Provides molecular parameters comparable to macroscopic mechanical properties.
Authors: Weiwei Tian, Hui Li, Yuqing Zhang
Institution: Southeast University
Language: English
Subfield: Civil and Structural Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: diamond
Awards: G1287159259, G6738378092, G8688614279
OpenAlex ID: W7129075844