The effect of surcharge pressure on the cyclic vertical deformations for expansive clayey soils in Morocco

The succession of wet and dry periods due to seasonal variations strongly influences the behavior of expansive clayey soils, and the negligence of this influencing parameter can compromise the long-term stability of structures built on these soils. To analyze this specific cyclic behavior, laboratory tests were performed during three wetting-drying successive cycles. In addition, the cyclic effect analysis was combined to the applied load effect in order to evaluate how the applied load can affect the cyclic behavior of expansive soils (clayey soil from the north of Safi, Morocco). It clearly appears that upon successive cycles, both swelling and shrinkage deformations decrease, and that the applied load modifies the soil behavior by reducing both deformations and soil kinetics.