An analytical solution for evaluating the progressive bending failure of columns in soft ground under embankment loading

Abstract

Rigid columns are commonly employed in soft clay embankment construction due to their high shear and bending capacities. However, conventional design methods often oversimplify the interaction between the columns and the surrounding soil by assuming uniform shear failure across all columns. This simplification can result in overestimations of embankment stability and may fail to account for potential unforeseen failures. In response to this limitation, the present study introduces a novel analytical framework, validated through centrifuge testing, to systematically assess the stability of soft ground reinforced with columns. Unlike conventional approaches, the methodology accounts for both bending failure mechanisms and progressive failure behavior during rapid embankment construction. It explicitly incorporates column-soil interaction, providing a more realistic stability assessment. Analytical expressions derived in the study quantify lateral forces exerted on the columns, offering insight into failure propagation from the embankment toe to the center. By integrating critical factors such as geometric parameters and soil properties, the methodology captures the variations in maximum bending moments, thus enhancing the predictive accuracy. This analysis of column progressive behavior enhances the understanding of embankment stability and provides a solid foundation for geotechnical design decisions.