A comparison of two and three dimensional finite element modelling of a geosynthetic reinforced pile-supported embankment

Embankment construction on soft ground has increased considerably over recent years as a result of the increase in infrastructure development activities and due to the unavailability of suitable land. Geosynthetic reinforced pile-supported (GRPS) embankments provide an effective and reliable solution to the problem of constructing embankments over soft ground. The combination of geosynthetic reinforcement and piles can alleviate the uneven surface settlements on the embankment crest while reducing the embankment load transferred to the soft foundation soil. This paper presents a numerical analyses based on the finite element method carried out on a GRPS embankment. Analysis was carried out in both two-dimensional plane strain condition for different two-dimensional idealisations of pile and in three-dimensional condition. The interaction between geosynthetic and soil was taken into consideration during the analysis. The results obtained for the two-dimensional models are compared with the three-dimensional model results. The stress transferred to the piles and foundation soil, development of settlements at the base of the embankment on both foundation soil and piles and the generation and dissipation of excess pore water pressures during and after construction for both two-dimensional and three-dimensional models are discussed.