The numerical modelling of geosynthetic-reinforced piled embankments using both the finite element method (FEM) and finite difference method (FDM) are compared. Plaxis 2D (FEM) was utilized to replicate FLAC (FDM) analysis originally presented by Han and Gabr on a unit cell axisymmetric model within a geosynthetic reinforced piled embankment (GRPE). The FEM and FED techniques were found to be in reasonable agreement, in both characteristic trend and absolute value. FEM consistently replicated the FDM outputs for deformational, loading, and load transfer mechanism (soil arching) response within the reinforced piled embankment structure with a reasonable degree of accuracy. However the FDM approach was found to give a slightly higher reinforcement tension and stress concentration but lower reinforcement strain at the pile cap than FEM, which was attributed to the greater discretize of the model geometry in the FDM than in FEM. 1. Introduction Special construction methods are required when embankments are constructed on very soft clay or peat. Design of embankments on soft ground raises several concerns such as bearing capacity failure, differential settlements, lateral stresses, and structural instability. Geosynthetic reinforced piled embankments are widely used to overcome these problems when constructing on soft soil. The geosynthetic-reinforced piled embankment (GRPE) structure consists of closely spaced piles which penetrate the soft soil to reach a stiff bearing substratum, the pile group is overlain by the geosynthetic reinforced, upon which the embankment is constructed, Figure 1. Han and Gabr [1] suggested the benefits associated with reinforced piled embankments are (1) single stage construction without prolonged waiting times; (2) significantly reduced differential settlements; (3) reduced earth pressures; (4) to avoid excavation and refill employed. Pile/column supported embankments improve structural stability and reduce embankment deformations [2–8]. The inclusion of geosynthetic reinforcement just above the pile caps enhances the load transfer efficiency, minimizes yielding of the soil, and reduces total and differential settlements, Han and Gabr [1]; Russell and Pierpoint [9]; Varuso et al. [10]; Rowe and Li, [11]; Bergado and Teerawattanasuk [12]; Brian？on and Villard [13]; Li and Rowe [14]; Rowe and Taechakumthorn [15]; Abusharar et al. [16]. Figure 1: Typical geosynthetic reinforced piled embankment. The design of reinforced piled embankments is a complex soil-structure interaction problem involving embankment fill, geosynthetic
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