Soft clay layers beneath embankments can lead to slope instability and excessive settlement under loads. This study investigates the use of polyurethane (Pu) foam piles as partial vertical replacements within soft clay to reduce embankment consolidation. Three-dimensional numerical modeling using Abaqus software was conducted to evaluate slope stability, considering soil shear strength parameters and allowable slope settlement. The effectiveness of Pu-Foam piles as a ground improvement technique was assessed, and practical insights were provided for optimizing pile configurations for safer and more reliable embankment design. Design charts were developed from comprehensive modeling results to assist engineers in evaluating slope safety factors. Results indicate that Pu-Foam piles should reach firm soil, with an optimum improved area ratio of 40–50% and a stress sharing ratio up to 90%.