Limit equilibrium slope stability analysis of column-supported embankment on weak ground

Abstract

PurposeThe study aims to analyse the stability of embankments over the improved ground with stone column (SC) and pervious concrete column (PCC) inclusions using limit equilibrium method. The short-term stability of PCC-supported embankment system is rarely addressed. Therefore, the factor of safety (FOS) of column-supported embankment system is calculated using individual column and equivalent area models.Design/methodology/approachThe stability analysis of column-supported embankment system is conducted using PLAXIS LE 2D. The various geometrical and shear strength parameters influencing the FOS of these embankment systems such as diameter of columns, spacing between columns, embankment height, friction angle of column material, undrained cohesion of weak ground and cohesion of PCC are considered.FindingsThe critical failure envelope of PCC-supported embankment system is observed to be of toe failure, whereas the failure envelope of stone column-supported embankment system is generally of deep-seated nature.Originality/valueIt is found that for PCC embankment system, FOS and failure envelope are not influenced by the geometrical/shear strength parameters other than height of embankment. However, for stone column-supported embankment system, FOS and failure envelope are dependent on all the shear strength and geometrical parameters considered in this study.