The pile-soil integrated element analysis method for laterally loaded pile in sand based on three-dimensional conical strain wedge model

Accurately simulating pile-soil interaction (PSI) is crucial for predicting the lateral behavior response of piles. For the three-dimensional nonlinear problem of pile-soil interaction, this study proposes an innovative three-dimensional conical strain wedge (3D CSW) model. The model’s conical characteristics and the tangential shear stress on the side surface can more reasonably describe the soil failure pattern and stress state. On this basis, virtual soil spring elements for describing the 3D PSI are integrated into the pile element at the Gaussian points to form the pile-soil integrated element. Its advantage is that the pile-soil integrated element effectively reduces the number of soil spring elements while accurately capturing the 3D PSI response, thereby improving the calculation efficiency for the laterally loaded pile. Validation and analysis suggest that the agreement between the results from the 3D CSW model and those from the full-scale field test and the centrifuge model test is generally satisfactory. The pile-soil integrated element analysis method requires only around 25% of the computational effort while maintaining sufficient accuracy. Through the discussion of the relevant parameters and influencing factors of piles and soil, the rationality and good applicability of the 3D CSW model and the pile-soil integrated element analysis method are further demonstrated.