Nonlinear analysis of laterally loaded single pile in layered soil based on conical strain wedge model

Abstract

The nonlinear analysis of piles subjected to lateral load is of significance for pile foundation design. In this paper, a novel conical strain wedge (CSW) model is proposed to simulate the pile-soil interaction and a nonlinear analysis of laterally loaded monopiles in layered soils is performed. The superiority of the CSW model is that it has higher accuracy in simulating stress states of the soil by taking into account the tangential shear stress around the front surface of the wedge soil and its circular cross-section is more consistent with the failure pattern. The efficiency and accuracy of the proposed CSW method are verified by comparison with the measurement results of four field tests, including sandy soil, normally consolidated (NC) clay and over-consolidated (OC) clay cases. Finally, a comprehensive parametric study is conducted to investigate the sensitivity of some input parameters. The results indicate that (1) the correction factor of the mobilized friction angle for different soil types is recommended as 0.2. (2) as the lateral load rises, the soil mobilized friction angle at various depths increases and tends to the ultimate friction angle. Under the same load situation, the soil mobilized friction angle decreases as depth increases. (3) the pile deformation is significantly influenced by the burial depth ratio of the pile.