刚性桩复合地基路基绕流滑动稳定分析

Stability analysis of flow-slide of embankment on rigid-piles composite ground

针对整体滑动稳定性满足规范要求的部分刚性桩复合地基路基发生滑塌的现实,分析了刚性桩复合地基路基可能的破坏模式,指出桩间荷载较大且桩间土软弱时可能会发生绕流滑动破坏,对刚性桩复合地基路基建议同时进行整体滑动稳定分析、绕流滑动稳定性分析和毁桩验算等。分析了刚性桩对滑动体的作用力并给出了相应的计算方法,通过对路堤荷载进行折减处理以及将桩周摩擦力转换至加固区地基土重度等措施,提出了绕流滑动稳定分析简化方法。工程实例表明,该方法合理可行。基于刚性桩复合地基路基绕流滑动稳定分析,对路基下刚性桩复合地基设计提出了建议。

Since some embankments improved by rigid-pile composite ground slid although their safety factors of overall stability meet the requirements of the codes, the possible failure models of embankment on rigid-pile composite ground are analyzed. It points out that flow-slide may occur if load among piles is large and soil among piles is soft. It is proposed that stability analysis of overall slide, stability analysis of flow-slide and check of flexural capacity of rigid-piles should all be carried out. The pile force to sliding body is analyzed and the calculation method is advised. Simplified method for stability analysis of flow- slide of embankment on rigid-pile composite ground is put forth on the basis of reducing the embankment load, converting the pile friction force to soil weight and other simplified measures. The simplified method for stability analysis of flow-slide is proved reasonable and practicable. Proposals for rigid-pile composite ground are put forward based on the analysis of flow-sliding stability of rigid-pile composite embankment.