Granular columns encased with geosynthetic material are commonly used to reduce the total deformations and to improve the load carrying capacity of very soft soil deposits (su< 15 kPa) underneath the embankments (Almeida et al. 2018). In this study a series of numerical analysis is performed using Plaxis 2D finite element code, aiming to investigate the influence of the encasement stiffness J, area replacement ratio ac, coefficient of at-rest earth pressure K0, and friction angle c of the column filling material on the settlement development and the column horizontal deformation (i.e. geotextile expansion). The data available from a full-scale load test is used to perform the finite element analyses on which geotextile-encased granular columns (GEC) stabilized 10 m-thick very soft soil (Almeida et al. 2015). Results of the parametric analyses showed that the increased friction angle of the column material reduced rather the geotextile expansion than the embankment settlement. Increasing either the encasement stiffness or the column diameter was also found to reduce remarkably both the settlement and the geotextile expansion. The differential settlements at the base and on the top of the test embankment were also compared while the area replacement ratio ac changed. The results demonstrated that the differential settlement at base of the embankment was associated with ac values.
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