Pullout capacity of a reinforced soil in drained and undrained conditions

A finite element model is built to analyse the pullout capacity of a stiff inclusion embedded in a soil matrix under both drained and undrained conditions. The influence of several parameters, including soil/reinforcement friction and vertical stress, on the pullout capacity of clean and silty sands reinforced with a steel strip is investigated. The ratio of undrained to drained pullout capacities ranges approximately from 0.58 to 0.89 depending on the interface friction coefficient and vertical stress. The most important factor for the pullout capacity in both drained and undrained conditions is the coefficient of friction at the interface. Other parameters such as the relative density of the sand, the overburden pressure, the coefficient of lateral pressure, or the soil model used, have a relatively smaller effect.