High-Temperature Rheological and Molecular Dynamics Analysis of Asphalt Modified with SiC Filler

Area of Science:

• Materials Science
• Civil Engineering
• Chemical Engineering

Background:

• Asphalt pavements face performance degradation under high-temperature environmental demands.
• Enhancing the high-temperature durability of asphalt is crucial for extending pavement service life.
• Silicon carbide (SiC) ceramic micropowder is explored as a potential modifier for asphalt.

Purpose of the Study:

• To investigate the effect and mechanism of SiC ceramic micropowder on modified asphalt performance.
• To analyze the rheological properties and modification mechanism of SiC-modified asphalt.
• To provide theoretical support for SiC application in high-temperature asphalt environments.

Main Methods:

• Saturates, Aromatics, Resins, and Asphaltenes (SARA) fraction analysis.
• Viscosity tests, dynamic shear rheological (DSR) tests.
• Fourier transform infrared spectroscopy (FTIR) and molecular dynamics (MD) simulations.

Main Results:

• SiC micropowder significantly improves asphalt viscosity and high-temperature stability due to its porous structure.
• Rheological tests showed a 34.74% improvement in G*/sin δ at 60 °C, indicating enhanced rutting resistance.
• FTIR confirmed a physical modification process; MD simulations revealed negative interfacial energy and selective adsorption of SARA fractions by SiC.

Conclusions:

• SiC ceramic micropowder effectively enhances asphalt viscosity and high-temperature performance through interfacial interactions and selective adsorption.
• The modification is a physical process, altering asphalt composition by promoting aggregation on the SiC surface.
• Findings offer valuable insights for the engineering application of SiC in high-temperature asphalt pavement construction.