Settlement control of high-speed railways is a key technology in embankment engineering. In order to reveal the engineering characteristics of the deep, completely decomposed granite soil in the Hainan East Ring Railway, four groups of centrifuge model tests were conducted. We studied the settlement properties, under the embankment action, of untreated subsoil, subsoil treated by dynamic compaction, and subsoil reinforced with cement-mixed piles. In particular, we examined the relationship between settlement and time, including the settlement during and after construction. The results show that the Weibull model can describe the relationship between embankment settlement and time well, and that the post-construction settlements of the subsoil meet the requirements of the relevant code. Among the two foundation treatment measures, dynamic compaction is more effective than reinforcement with cement-mixed piles. The tested pressure on the contact surface between embankment and subsoil was obviously different from the commonly used calculated values. Settlement control of high-speed railways is a key technology in embankment engineering. In order to reveal the engineering characteristics of the deep, completely decomposed granite soil in the Hainan East Ring Railway, four groups of centrifuge model tests were conducted. properties, under the embankment action, of untreated subsoil, subsoil treated by dynamic compaction, and subsoil reinforced with cement-mixed piles. In particular, we examined the relationship between settlement and time, including the settlement during and after construction. the Weibull model can describe the relationship between embankment settlement and time well, and that the post-construction settlements of the subsoil meet the requirements of the relevant code. Among the two foundation treatment measures, dynamic compaction is more effective than reinforcement with cement-mixed piles. The tested pressure on the contact surface between embankment and subsoil was obviously different from the commonly used calculated values