Numerical study on the effect of pile shape and loading direction on the lateral response of displacement pile in sand.

Several finite element numerical simulations were conducted on laterally loaded piles in Geba sand to investigate how pile shape, loading direction, and pile length impact lateral load transfer curves and pile-soil interaction. The stress-strain behavior of Geba sand was defined using the hypoplastic constitutive model within the finite element software via the UMAT subroutine. The accuracy of the finite element model was confirmed through a comparison with the centrifuge test findings from prior research. Using the validated finite element model, we examined the behavior of circular and square piles subjected to lateral loads at 0° and 45° angles. The findings indicate that square piles exhibit greater lateral bearing capacity compared to circular piles. The change in the loading direction of square piles changes the pile-soil interaction mode. Square piles with a loading direction of 45° can mobilize a wider range of soil, therefore, the lateral bearing capacity is higher than that of 0° loading direction. The increase in pile length changes the deformation mode of the pile, which can significantly reduce the influence of the shape and loading direction of the pile on the deformation of the laterally loaded pile. When the pile length exceeds 7D, the deformation of the pile below the depth of 6 m is almost 0.