Characterization of nanoscale cracking at the interface between virgin and aged asphalt binders based on molecular dynamics simulations

Journal article (2022)

Authors

Yohannes L. Yaphary The Hong Kong Polytechnic University
Zhen Leng The Hong Kong Polytechnic University
S. Ren Pavement Engineering - CEG
Guoyang Lu The Hong Kong Polytechnic University
Research Group
Pavement Engineering (CEG) (TU Delft)
Copyright: © 2022 Yohannes L. Yaphary, Zhen Leng, Haopeng Wang, S. Ren, Guoyang Lu
DOI
help_outline
https://doi.org/10.1016/j.conbuildmat.2022.127475
More Info
expand_more

Published Date

2022

Language

English

Reuse Rights

Other than for strictly personal use, it is not permitted to download, forward or distribute the text or part of it, without the consent of the author(s) and/or copyright holder(s), unless the work is under an open content license such as Creative Commons.

Faculty

Civil Engineering & Geosciences

Department

Engineering Structures

Research Group

Pavement Engineering

Abstract

Low-temperature cracking is a major concern to improve the utilization of recycled asphalt mixture (RAM). A mechanism by which the crack propagates can provide a basis for advanced technological mitigation. Microcrack formations in the interfacial proximity of the virgin and aged binders have been identified from electron microscopy tests. Atomic force microscopy (AFM) experiment showed the trilayer phases at the virgin-aged binder interface. In this study, molecular dynamics (MD) simulations were conducted to understand the nanoscopic
crack propagation characteristics at the virgin-aged binder interface in the asphalt mixture with RAM. It was found that the blended binder of virgin and aged binders, and its interfaces with virgin and aged binders appeared to be the crack propagation zones. The relatively more significant matrix contraction of virgin binder and stiffer aged binder at a low temperature can cause more considerable tensile stress at the blended binder and its interfaces. Consequently, interfacial crack propagation became more profound and decreased the low temperature cracking resistance.