Performance evaluation of the embankment subject to climate change and dynamic train loads is important to the safety of high speed railway (HSR). In this study, based on an elasto-plastic unsaturated soil model, a coupled hydraulic-mechanical-air finite element analysis method is proposed, which integrates the analysis under rainfall condition and the analysis under dynamic load in one numerical simulation. A finite element analysis program called DBLEAVES-X is improved from its previous version (DBLEAVES) to consider the hydraulic-mechanical-air coupled behavior in unsaturated soils under dynamic condition. In order to verify the feasibility of the proposed method, a reduced-scale model test was first simulated. The calculating results showed that the measured displacement and acceleration can be well reproduced by the proposed method. Analyses on the effect of rainfall conditions, train loads and embankment materials were then conducted for a full scale prototype model of typical HSR embankment. The results of the analyses show that higher intensity of rainfall infiltration increases the risk of local failure. A higher train speed and heavier train axle load result in larger displacements. The frequency of the acceleration response is only influenced by the train speed. The embankment performance worsens with the degradation of the embankment material. Preceding rainfall condition results in a larger displacement of the track slab after the dynamic load is applied.

受气候变化和列车动态载荷影响的路堤性能评估对高速铁路（HSR）的安全性至关重要。本研究基于弹塑性非饱和土模型，提出了一种水力-机械-空气耦合有限元分析方法，该方法将降雨条件下的分析与动荷载下的分析相结合为一个数值模拟。名为DBLEAVES-X的有限元分析程序在其先前版本（DBLEAVES）的基础上进行了改进，以考虑动态条件下非饱和土壤中的水力-机械-空气耦合行为。为了验证该方法的可行性，首先模拟了缩小模型测试。计算结果表明，所提出的方法可以很好地再现所测得的位移和加速度。然后，针对典型高铁路堤的完整原型模型，进行了降雨条件，火车荷载和路堤材料的影响分析。分析结果表明，较高的降雨入渗强度增加了局部破坏的风险。较高的列车速度和较重的列车轴负载会导致更大的位移。加速度响应的频率仅受列车速度的影响。随着路堤材料的降解，路堤性能变差。在施加动态载荷后，前面的降雨条件会导致轨道平板的位移更大。分析结果表明，较高的降雨入渗强度增加了局部破坏的风险。较高的列车速度和较重的列车轴负载会导致更大的位移。加速度响应的频率仅受列车速度的影响。随着路堤材料的降解，路堤性能变差。在施加动态载荷后，前面的降雨条件会导致轨道平板的位移更大。分析结果表明，较高的降雨入渗强度增加了局部破坏的风险。较高的列车速度和较重的列车轴负载会导致更大的位移。加速度响应的频率仅受列车速度的影响。随着路堤材料的降解，路堤性能变差。在施加动态载荷之后，前面的降雨条件导致轨道平板的位移更大。