Analytical Solutions for Ultimate Stabilizing Action of Anchored Piles in Cohesive Soil Layers

The design of slope-stabilizing piles is still an open issue for civil engineers, owing to the high number of variables to be determined in the design process and to the complexity of soil-structure interaction problems. In this paper, in the simplified case of subhorizontal cohesive soil strata, analytical solutions are proposed for the maximum available stabilizing action for a pile, also considering the possible presence of an anchor at the pile's head, and thus extending some results already available in literature. Within the framework of an ultimate limit state approach, the influence of soil mechanical properties, of pile characteristics, and of the anchor strength are investigated, and some dimensionless abaci are analytically derived. The solutions demonstrate a marked coupling effect between tensile anchor strength and pile-bending resistance, and an explicit optimization strategy for a safe and effective dimensioning is provided. The results can be profitably employed in the most common limit equilibrium methods for slope stability analysis.