A Simplified Method for Relating Rainfall to Movements of Slopes Reinforced by Piles

Using one or more rows of piles embedded in the stable portion of a slope is usually recognized as a suitable measure for slope stabilization. However, the landslidemight be still reactivated due to a significant raising of the groundwater level caused by rainfall. In this context, a simplified methodology is presented in this paper to predict the rainfall-induced movements of landslide bodies in the presence of stabilizing piles. Specifically, the proposed method uses a water balance equation to relate rainfall to groundwater level changes, and an equation of motion of a two-block system representing the landslide body, to relate these changes to the landslide movements, accounting for the passive resistance exerted by the piles. This latter force can be evaluated on the basis of the pile arrangement and the possible pile-soil failure mode using some practical solutions available in the literature. The application of the method to an ideal case study is presented to show the effects of the stabilizing piles on the landslide mobility.