While highways in mountainous regions frequently employ part-fill and part-cut subgrades with diverse formation mechanisms, frequent distress occurrences expose a gap between current engineering practices and theoretical design principles. This review aims to find an integrated approach for the analysis and design of part-fill and part-cut subgrades and pavement structures by collecting and organizing relevant research methods, data, and conclusions. For this purpose, Sect. 2 provides an overview of analytical methods and key influencing factors for the stability of part-fill and part-cut subgrades. The uncertainty of the position and shape of the sliding surface makes the strength reduction method (SRM) a more suitable stability analysis method. Recognizing differential settlement as a critical factor in the performance of pavement systems constructed on these subgrades, Sect. 3 examines recent advancements in testing and simulation techniques for evaluating differential settlement patterns. While both tests and simulations reveal "spoon"-shaped differential settlement patterns, practical analyses often simplify these to linear or parabolic shapes. Section 4 investigates the impact of differential settlement on both asphalt and concrete pavement structures, drawing upon established understanding of settlement characteristics. Section 5 reviews proposed control indexes and standards for managing settlement differentials, resulting in a three-tiered approach to control indicators: maximum differential settlement, differential settlement slope rate, and bending degree of differential settlement curve. Finally, Sect. 6 identifies key future research directions for a fully integrated approach for analyzing and designing part-fill and part-cut subgrades and pavement structures, offering valuable insights to enhance design technology in this domain.
