Numerical Investigation of the Behavior of Group-Finned Piles in Sandy Soil Subjected to Tensile Loads

Abstract

Numerous towering structures such as dock-fendering systems, abutments, marine dolphins, transmission towers, and high-rise platforms, which experience substantial uplift loads, rely on deep foundations for support. In this research, we have introduced an innovative pile modification technique aimed at enhancing traditional piles, known as the "finned pile." This modification involves the addition of four fins, welded around the lower circumference of the pile, to augment its tensile capacity. Numerical simulations were conducted to subject various pile groups and spacing configurations to axial static tension loading. Throughout all test scenarios, consistent parameters such as fin width, fin length, number of fins, embedment depth, and pile diameter were maintained to assess the effectiveness of this pile modification strategy. The analysis utilized the PLAXIS 3D Foundation as its numerical modeling program. The findings demonstrated a noteworthy enhancement in the uplift capacities of pile groups with fins when compared to traditional piles without fins. For finned pile groups featuring different L/d ratios of 10, 20, and 26, the respective capacities reached 450 Kg. Conversely, the normalized displacement ratio exhibited an uptick with higher L/d ratios, measuring 0.4, 0.9, and 4.4, respectively. Consequently, there was a marginal performance improvement in finned pile groups with increasing ratios. Moreover, the performance of the pile groups saw a significant enhancement as the soil Dr (Relative Density) increased. For varying Wf (Finned Pile Width), the ultimate load of finned pile groups showed a slight rise with increasing Wf while keeping the fin length constant. In contrast to single fin piles, Wf exhibited an increase as the ultimate load rose.