Passive earth pressure due to surcharge loading under three modes of wall movement

Passive earth pressure behind retaining walls under rotational movements has been widely investigated recently. However, the behavior of surcharge loading under rotational movement has not been fully explored in the literature. This paper numerically investigates the impact of different types of wall movement; translation, rotation about the top and rotation about the bottom, on the two and three-dimensional passive earth pressure due to uniform surcharge loading. Results prove that the limit pressures under rotational mode are significantly lower than those in translational mode, ranging from 63% to 98% of those used in the literature. Overestimating coefficients in the design of retaining structures can lead to insecurity and instability. Furthermore, the distribution of passive earth pressure with depth is no longer rectangular. Shape factors are then evaluated to facilitate the practical application of passive earth pressure coefficients under rotational wall movements.