Abstract: This study investigated the evolution of soil arching within a pile-supported and geogrid-reinforced embankment using a three-dimensional finite element model. The results were verified through a comparison with the measured data obtained from a full-scale experiment. The development of the soil arching was evaluated during the embankment construction process and the static step-loading process. The study revealed that the stress concentration ratio between the average stress on the pile-cap and that on the subsoil increases with the increasing height of the embankment fill. But this ratio increased little during the static step-loading process. In the soil arching process, the arch foot was mainly located at the edge and corner, not the center of the pile-cap. This resulted in an uneven stress distribution on the pile-cap, with stress at the edge and corner larger than that at the center. With the increase of embankment filling height and the evolution of soil arch, the arch foot moves towards the center. The critical height of the soil arching is 1.3 to 1.4 times the net spacing between pile caps. Additionally, the arching heights were assessed at different locations of the embankment, and their values were approximately equal.

Key words: finite element model, Pile-Supported and Geogrid-Reinforced Embankment, Soil arching