Nonlinear analysis of horizontal bearing capacity of large-diameter rigid piles based on double conical strain wedge model

Large-diameter rigid piles are commonly employed in offshore wind turbine installations. A double conical strain wedge (DCSW) model is proposed in this paper to simulate the large-diameter rigid pile-soil interaction and determine the lateral subgrade reaction. A nonlinear analysis method is developed to predict horizontal response for large-diameter rigid piles installed in layered cohesionless soil, which can account for the effect of vertical side shear stress, pile end bending moment, and shear force. The rationality of the DCSW model is then verified by comparing its predictions with the experimental and theoretical results of existing studies. Subsequently, the new DCSW method is applied to investigate the horizontal bearing characteristics of the large-diameter rigid piles. The results reveal the presence of a rotation point situated at a depth range of (0.66-0.76) Lb (Lb is the burial depth of the pile). Additionally, the resisting bending moment caused by the vertical side shear stress between the pile-soil interface is able to enhance the horizontal bearing capacity of the pile.

Automated summary

In this paper, a double conical strain wedge (DCSW) model is proposed to simulate the large-diameter rigid pile-soil interaction and predict the lateral subgrade reaction. A nonlinear analysis method is developed to consider the effect of vertical side shear stress, pile end bending moment, and shear force on the horizontal response of large-diameter rigid piles in layered cohesionless soil. The rationality of the DCSW model is verified by comparing its predictions with experimental and theoretical results. The study also reveals the presence of a rotation point at a certain depth range and the ability of vertical side shear stress to enhance the horizontal bearing capacity of the pile.