复合地基加固路堤的稳定性分析

通过对复合地基加固路堤稳定性的极限平衡法和有限单元法的计算结果进行对比分析，揭示出当路堤的稳定性由复合地基决定时，极限平衡法和有限单元法的计算结果存在较大差异。应用岩土有限元软件Plaxis中的强度折减法可得到合理的路堤稳定性分析结果。对复合地基中桩体破坏模式的分析认为，桩体发生非剪断破坏之外的弯曲、转动、拉伸等破坏模式是极限平衡法与有限单元法计算结果产生差异的根本原因。由此进一步指出，当处理存在土与结构物相互作用的边坡稳定问题时，极限平衡法的分析结果可能会高估了边坡的稳定性，应慎重判别其合理性。

Stability analysis of embankment on composite subgrade

Based on comparative analyses of slope stability of embankment on composite subgrade by using limit equilibrium method and finite element method, it is revealed that the calculated safety factors by LEM and FEM can be significantly different when the reinforcements in composite subgrade have dominating influence. Embankment stability can be well predicted by strength-reduction method by using plaxis software. It is further investigated that for embankment on composite subgrade the potential failure patterns of reinforcement columns such as bending, rotation and extension, other than direct shearing through reinforcements, made the difference in calculated safety factors by LEM and FEM. Therefore, for embankment stability analysis with interaction between soil and reinforcement in composite subgrade, LEM may overestimate slope stability and its applicability should be checked with caution.