Numerical Study on Deformation Characteristics and Influencing Factors of Super-High Filled Subgrade

Super-high filled subgrades are a critical component in highway construction, especially in mountainous or uneven terrains where establishing a stable and even road surface presents significant engineering challenges. The stability and deformation behavior of such structures under the influence of various factors are of paramount importance for ensuring the longevity and safety of the transportation network. Based on the numerical simulations, the effects of filling height, slope grade, and the wide platform on the deformation characteristics of a super-high filled highway subgrade are discussed. The results showed that with the increase of the filling height, both the settlement and the horizontal displacement of the subgrade gradually increased. Due to the natural ground is inclined, the subgrade settlement and horizontal displacement exhibited asymmetric. After the subgrade filling was completed, the overall settlement tended to be smaller on the left and larger on the right, with the maximum settlement occurring at the thicker filling area; while the horizontal displacement decreased from the top to the bottom of the embankment, and the maximum horizontal displacement occurred within a certain distance to the left of the centerline of the road surface. The position of the maximum horizontal displacement at the top of each embankment level developed gradually from left to right. The reduction of slope grade and the setting of a wide platform at the base of subgrade both contribute to reducing the settlement and horizontal displacement, and the influence of slope grade on the maximum horizontal displacement of the subgrade is greater than its effect on the maximum settlement.