Nonlinear Response of Micropile Groups Stabilizing Landslides Considering Pile–Soil Interactions

Methods for analyzing micropile groups considering complex pile–soil interaction have received less attention. This paper proposes a calculation method to study the internal force of micropile groups considering shadow effects of pile groups and nonlinear soil pressure. The nonlinear load transfer mechanism of micropile groups based on the concept of p-multipliers is studied, and the relationship between the p-multipliers of nonlinear landslide thrust and soil resistance and the normalized pile spacing are established. The new governing equations and calculation models of the micropile groups considering the possible failure modes and the p-multiplier method are established. Finally, the proposed method is verified by two case studies. The study results show that the established p-multiplier model of landslide thrust and soil resistance is closely related to soil properties and normalized pile spacing. Comparing the measured results, it is noted that the newly proposed model improves accuracy by an average of 29% over the traditional method. The effect of bending stiffness on the internal forces of piles is more significant than the normalized pile spacing.