Third National Conference on Geosynthetics, İstanbul, Turkey, 13 - 14 November 2008, pp.155-166
Use of column-supported embankments for construction over soft ground is increasing due to the increasing demands for accelerated construction. Furthermore, such an approach results typically in a more reliable solution in terms of controlling settlements. To minimize differential settlement between the support columns and the ground between them, a geosynthetic-reinforced load transfer platform (GRLTP) is typically placed at the base of the embankment. Most numerical analyses of such platforms have been two-dimensional (plane strain) with some adjustments, e.g., reducing column rigidity proportional to column spacing. The column-GRLTP system is numerically modeled using the 3-dimensional version of PLAXIS, a widely used numerical analysis code, for different column lengths, spacings, and rigidities for a set of typical soft ground parameters. The calculated arching ratios are compared with those from the 2-dimensional modeling using the same parameters and with those reported in the literature. A higher arching ratio is obtained from the 3-dimensional analysis compared to 2-dimensional analysis even after making an adjustment by reducing column rigidity in the latter.