Improved Analytical Method for Stabilizing Piles in Loess Slope Considering Nonlinear Pile-Soil Interactions

In loess slopes, landslides are easily caused by rainfall and can be prevented by using retaining structures of stabilizing piles. This paper investigated the deformation and mechanical behaviors of the cantilever and fully buried stabilizing piles under complex pile-soil interactions. The deformation and mechanical behaviors, failure modes, and soil pressure distributions of two types of stabilizing piles were analyzed based on field model tests. Further, a calculation method for stabilizing piles considering nonlinear pile-soil interactions was proposed. Also, the numerical solution of the pile deformation and force was obtained by using the finite difference method and Newton's iterative method. The results showed that the deformation and mechanical behaviors of fully buried piles are superior to those of cantilever piles. Fully buried piles and cantilever piles have plastic double-hinged and single-hinged failure modes and undergo bending damage and shear damage, respectively. Besides, the landslide thrusts and soil resistances acting on the pile showed a parabolic distribution pattern. Compared to the model test results, the traditional calculation method overestimated the deformation and internal force of the stabilizing pile by 37.32%, and the newly proposed calculation model considering nonlinear pile-soil interactions was more consistent with the measured values. The study results help to guide the design and calculation of stabilizing piles under complex pile-soil interactions.