This paper presents a comprehensive review on the fatigue damage of asphalt mixtures, specifically exploring the impact of varied air-void contents through microstructural analysis. The study synthesizes findings from existing research to elucidate the intricate relationship between air-void levels and the microstructure of asphalt pavements, ultimately influencing their fatigue performance. Employing advanced techniques such as scanning electron microscopy and X-ray computed tomography, the review examines the evolving landscape of research methodologies and their contributions. The correlation between air-void content, microstructural characteristics, and the initiation and propagation of fatigue cracks is systematically analyzed. The paper also discusses challenges in microstructural analysis and suggests future research directions. The insights gained from this review have practical implications for optimizing air-void content in asphalt mixtures, contributing to improved pavement durability and performance.

Fatigue damage, asphalt mixtures, air-void content, microstructural analysis, pavement performance.