列车荷载作用下地基动力及沉降特性分析

Dynamic Stress and Settlement Charateristics of Foundation under Train Load

为分析列车荷载作用下的地基动力及沉降特性,建立了轨道-路堤-地基在列车荷载作用下的动力耦合分析数值模型,考虑列车速度、路堤高度和基床刚度的影响,研究了列车荷载作用下的地基动应力分布及地表沉降特性,并对不同地基加固形式的加固效果进行了探讨。研究结果表明:列车荷载作用下地基动应力沿水平方向和地基深度迅速减小;地基竖向动应力和地基沉降随列车速度的增大而增大,随路堤高度和基床刚度的增大而减小,路堤高度不宜小于2 m;地基沉降随加固深度和加固区刚度增大而减小,列车速度越高,影响越明显,最佳地基加固深度为3 m。

In order to analyze the dynamic stress and settlement charcteristics of the foudation under train load,the dynamic coupling numerical model of rail-embankment-foudation interaction under train load was established,considering the effect of train speed,embankment height and base stiffness. The dynamic stress distribution of the foudation and settlement charcteristics of surface under train load were researched,and the reinforcement effect of different foundation reinforcement forms was discussed. The results show that the dynamic stress of foundation decreases quickly along the horizontal and vertical direction under train load. The vertical dynamic stress of foundation and foundation settlement increase as the train speed increases,while decrease with the increase of the embankment height and base stiffness. The embankment height should not be less than 2 m. The foudation settlement decreases with the increase of the reinforcement depth and stiffness of the reinforced area. The higher train speed,the more obvious effect; and the best foundation reinforcement depth is 3 m.