Granular encased columns (GECs) with geosynthetic are an effective technique for improving the soft soil foundation of embankments. One of the primary functions of GECs is to increase the bearing capacity of the soil, preventing foundation failure and eliminating the need for berms. GECs increase the soil’s bearing capacity, preventing foundation failure, eliminating the need for berms, and increasing the factor of safety. Two methods are recommended to integrate the geosynthetic strength with the original strength of the ordinary granular column: a) using the increased angle of friction ( ϕ’ sub ), or b) using the increased cohesion ( c’ sub ). Laboratory (direct shear tests), numerical (3D modeling) and analytical studies were conducted to investigate the accuracy of using ϕ’ sub and c’ sub to represent the increased strength parameters attributable to, resulting from to encasement. The results indicate that the strength of the composite column (sand + geosynthetic) can be adequately represented by the ϕ’ sub parameter for a wide range of geosynthetic stiffness ( J ). However, the approach using the c’ sub parameter did not yield satisfactory results, even for a broad range of J . Therefore, the use of the ϕ’ sub approach is recommended for stability analysis of embankments built on soft soils supported by GECs.