Stress-strain hysteresis shape estimation of different soils using deformation-history integral (DHI) model

Different soils show different nonlinear stress-strain patterns. Hence, it is difficult to come up with a general model to predict these shapes. This study investigated the suitability of the DHI model which was not originally formulated for geomaterials. This model was applied to different loading cycles of various types of soils and the model’s variables were optimized using nonlinear generalized reduced gradient (GRG) method. Up to five hysteresis springs were considered in the study. The computed error criteria indicated that the DHI model approximated the nonlinear hysteresis shapes appropriately and using three hysteresis springs presented the best estimation for almost all cases. In addition, this model approximated the initial loading cycles better than the final ones.