Abstract: Model tests on a single pile in sands with different densities are carried out by using a self-developed cyclic loading apparatus for a long term. A prediction model for cyclic cumulative displacement is established considering the influence of sand density, and its application scope is discussed. The regression analysis of model tests results reveals that the first cyclic cumulative displacement increases exponentially with cyclic load ratio, and the model parameters are related to the relative density of sand. The predicted values of cyclic cumulative displacement obtained by the power function model are consistent with the measured values within a certain level of cyclic cumulative displacement rate, but the cyclic cumulative displacement rate is associated with the sand density, therefore, the influence of the sand density on partition rule of cyclic cumulative displacement under cyclic axial loading should be considered.

Key words: single pile, cyclic axial loading, cyclic cumulative displacement, model test, sand density