Scour can cause the water-induced failure of fluvial and marine bridges and structures. Previous studies have focused on the scour mechanisms and their effects on the load capacity of single piles, although deep foundations consist mostly in pile groups. In this paper, scouring on pile groups embedded in soft clay is studied when piles are laterally loaded and affected by the formation of scour holes. This boundary problem is simulated using the three-dimensional finite element method. The scour depth, slope angle, and pile spacing are analyzed as main influence factors. Summary charts quantify how the dimensions of scour holes affect the lateral load capacity of 3x3 pile groups for varying pile spacing and their corresponding p-multipliers. Importantly, results indicate that it is unreasonable to design pile foundations by ignoring the influence of scour holes or directly removing the soil layer above the scour depth, as frequently assumed in practice.
