Creep behavior of slip zone soil of the Majiagou landslide in the Three Gorges area

Abstract

The creep properties of slip zone soil are critical to deformation prediction and slope stability analysis. A series of triaxial drained creep tests were conducted on the slip band soil from a creeping landslide. The results indicate that soil creep occurs in two stages, with confining and deviatoric stresses being critical factors. The long-term strength of the soil was estimated to be 60–75 % of the conventional strength according to the isochronous curves. The soil creep characteristics were used to predict the creep strain using both the Burgers and the Singh–Mitchell model, and large discrepancies were found between the predicted strain and test results. Accordingly, a new empirical model based on the Morgan Mercer Flodin growth model has been developed to describe the creep behavior of gravely clay in the slip zone. Four parameters of this model are estimated by nonlinear regression. The deformations predicted by this model are in reasonable agreement with experimental data.