Failure Modes for Geosynthetic Reinforced Column Supported (GRCS) Embankments

Deep cement mixed columns are widely used to support highway embankments constructed on soft compressible ground. Current design procedures for these embankments consider the sliding failure for external stability and the shear failure of deep cement mixed (DCM) columns for internal stability. Other failure modes such as collapse failure, slip circle failure, punching shear failure (overall or local) and bending failure of DCM columns are also significant for column supported embankments. However. still there are uncertainties in identifying the critical failure modes for these embankments. Hence, this paper investigates some failure modes for Geosynthetic reinforced column supported (GRCS) embankments using the finite element method. The embankment and traffic loads are gradually increased to bring the embankment to the verge of failure. Bending failure of DCM columns and subsequent shear failure for internal stability, local punching failure, overall punching failure and excessive total settlement failure are identified from the finite element analysis results and discussed in detail.