Atomistic-scale investigation of self-healing mechanism in Nano-silica modified asphalt through molecular dynamics simulation

Abstract As one of the most widely used nanomaterials in asphalt modification, nano-silica (nano-SiO 2 ) can significantly improve self-healing behavior eco-friendly. However, understanding mechanism nano-SiO is still limited. The objective study to reveal by using molecular dynamics (MD) simulations from nanoscale. A 10 Å (Å) vacuum pad was added between two same stable models represent micro-cracks inside asphalt. process virgin asphalt, oxidation aging and modified studied density evolution, relative concentration, diffusion coefficient, activation energy, pre-exponential factor. simulation results conclude that improves ability increasing rate molecules with aromatic structures without alkyl side chains longer chains. capability may be principally determined light components such as saturate, while only plays an inducing role. research findings could provide insights understand for promoting sustainability bitumen pavements their durability. Graphical abstract