An Experimental Study on Laterally Loaded Winged Pile in Sandy Soil

Many offshore facilities such as offshore wind turbines and other engineering structures, including floating offshore facilities (FPSOs), are founded on or anchored with piles to transfer large horizontal loads relative to the imposed vertical load compared to onshore installations. The subgrade reaction of the soil surrounding the pile shaft mobilized when the lateral loading is applying on the pile to resist the applied loads. Since the soil at the midline is often weak and tends to have a poor subgrade reaction, resulting in large pile displacements near ground level. The lateral bearing capacity of pile foundations can be increased, and pile displacements near ground level can be decreased by expanding the piles' cross-sectional area near the seabed level to compensate for the lower soil stiffness in the seabed level. One method of expanding the pile area in the lower soil stiffness zone is the addition of wings (or fins) near the seabed level. This paper presents a series of laboratory small-scale model tests that were conducted to laterally loaded piles with/without wings in sandy soil with different densities. The Piles slenderness's ratio (L/D) is varied from 4, 6, 8, and 10 to simulate the behavior of both flexible and rigid pile designs, with different wings geometry and numbers. This study indicated that the lateral pile capacity increased, and the horizontal deformation of the pile decreased after mounting wings compared to the regular normal pile without wings. It has been found that the optimum geometry and number of adopted wings is found to be three wings, and its length equals (0.22) of the embedded pile length. The existence of wings improved the bearing capacity of the winged pile by 1.33, 1.18, and 1.16 for piles of L/D=10 in the case of loose, medium, and dense soils, respectively, compared to regular piles in the same condition.