Practical Calculation Method for Stability of Embankment on Soft Subgrade Reinforced with Unreinforced Rigid Piles

In order to reasonably evaluate the stability of embankment supported on composite ground reinforced with unreinforced rigid piles,based on the study of the failure mechanism of embankment on soft subgrade reinforced with rigid piles,different simplified stability analysis methods were suggested and compared with traditional method by performing numerical analysis of three typical examples of embankment.The results indicate that embankment stability can be highly overestimated when using the traditional method and the equivalent shear strength method can better reflect the failure mechanism of embankment reinforced with rigid piles.The safety factors by the equivalent load method and the equivalent sand pile method are fairly close to that by the equivalent shear strength method.The pile-soil stress ratio has great influence on the safety factors with the BS 8006 method,the equivalent load method and the friction contact method.It is suggested that more than one simplified method be used when performing the overall stability analysis for embankment supported on composite ground reinforced with unreinforced rigid piles in order to ensure the redundancy of the design.