Sustainable asphalt: self-healing and its impact on fatigue life and damage model

Abstract

ABSTRACT Asphalt mixtures are frequently used for highway pavements, with fatigue damage occurring over time. Although numerous fatigue damage models have been proposed in academia, none account for the influence of asphalt mixtures’ self-healing characteristics on their fatigue processes. The present paper examines the self-healing effect of multi-factor asphalt mixtures on the fatigue process from a mechanical perspective. The original model is revised, and the influence of the correction coefficient is introduced, leading to the proposal of a fatigue model of asphalt mixtures that considers multi-factor self-healing effects. The model’s accuracy is verified through four-point bending fatigue tests on various grades of asphalt mixtures. The findings demonstrate that the self-healing properties of asphalt blends have a distinct positive impact on fatigue progression and endurance when considering temperature, strain strength, initial damage rate, and healing time. Furthermore, after experimental validation and model analysis, the adjusted model, which includes the self-healing effect, provides a more precise account of the fatigue life of asphalt blends. Furthermore, the experimental analysis yielded the performance characteristics of asphalt mixtures with varying coarse and fine aggregate gradations.