Analytical solutions for the stability of stone column-supported and geosynthetic-reinforced embankment

This study presents a novel prediction model based on the three-wedge method, utilizing a force-based equilibrium model to evaluate the stability of embankments reinforced by stone columns and geosynthetics. The proposed model utilizes six slip surfaces, enabling it to accommodate diverse geometric configurations, shear strength parameters, reinforcement arrangements (i.e., stone columns and geosynthetic), surcharge, water level, and quasistatic seismic coefficients. A constant factor of safety is initially assumed for each slip surface and reinforcement element, although this assumption can be relaxed by varying the strength parameters. The factor of safety is determined analytically through the solution of a polynomial equation. The proposed analytical solutions, which offer a compact form, provide new insights for the three-wedge method and effectively customize the conditions for geosynthetic-reinforced column-supported embankment applications, characterized by wedge interaction between the embankment, clay, geosynthetics, and columns. Validations of the proposed method are performed using the results obtained from the centrifuge test and numerical modelling, demonstrating the reliability of the analytical solution.